I'm surprised by that statement. Last year I played several sessions of Civ 1, without using the manual, and was surprised by how simple and comprehensible the rules are. With the information the game openly provides you can quite easily figure out the underlying mechanics. Maybe I didn't get all of it but I certainly didn't feel like there was important stuff going on that I don't understand.

Of all the civilization games i played i found civ 3 the most easy to get into, i just loved it when it came out still play it there are some annoying mechanics(corruption) but its way easier to get into and play and there are tons of mods. Just love the graphics of civ 3 still holds up well.
It was much easier to setup and go on civ 3 than 4.

Civ 4 almost made me quit the series , there was a lot of things to take in and the interface never suited me at all , The annoying stacks of death made the gaming sessions and management a hell.

Religion is also something that frustrated me a lot

Civ5 brought me back to the fold , If you can grab the complete edition of civlization 5 it is amazing to play with its great expansions. It has a lot of throwbacks to civ3

I have always been the odd man to like in the civilization series for the best civlization games i can play any time are

civ1(snes) -> civ 3 -> civ5

I found the even series to have too much steep learning curve and dull graphics so i avoid

civ 2 -> civ4 -> civ6


If you can pick up both and try it out , they go on very deep discount sales.

I've played Civ 1-4. I really enjoyed 2, but out of 3 and 4, I'd go for 4 every time. The developer notes in the manual sum it up for me - the focus was on removing or changing the things that weren't fun. Like corruption.

I also really love the graphical style.

I admit, I also don't have the patience for how slow going Civ I often feels, with discoveries and building taking as long as they do; with settlers being required for tile improvements and all.

I played all civilization games till civ 5. Will not touch civ 6.

Civ 1 :
was a great game at that time. But it had some serious flaws.
-> units had no hitpoints pool. So if you placed a settler on a mountain next to an water tile
and there was an enemy battleship. The settler could sink the battleship if the battleship attacked and failed.
To make it more funny the settler had a combat strength of 0 (ZERO).

Civ 2 :
improved the gameplay a lot. Units now had 100 hitpoints. That made combat much better.
And the advisors were actors, and really great and very funny ones ( Remember Elvis ? Or the drunken singing Military Advisor when your army was the strongest ). Great Wonder movies, a throne room that you could improve, and many other things made this game awesome.

Call to Power 1 :
Good game. But with to many strategic layers. Infrastructure Point system.

Civ 3 :
A big step back from Civ 2 for me. I liked to settle a lot and Civ 3 punished me for that. Could upgrade my units. Think I remember a map/scenario editor. Another bad point was that the special resources could ran out. Happened to me a few times that there was no longer oil available on the map.

Call to Power 2 :
A very great game. What I really like is that I need no workers to build roads/railroads/...
You get infrastructure points and use them. So no longer 80+ worker units upgrading streets to railroads and such stuff.
The layers are reduced to one. No longer switching between orbital and ground combat. Nice wonder movies. Only thing I missed in the call to power games is the throne room and tha ability to upgrade units. The new "upgrade units" ability that entered the Civ Games with Civ 3 and a throne room would have made this game the best till today.

The Call to Power games are more moddable than the early civ games.

Civ 4 :
A big step forward from the not so good Civ 3. But again I got punished for building many cities. Wondermovies are bad, only two good movies in game. No Infrastructure Points system, again 80+ workers...
But it got great modding abilities. So I was able to change a lot and build again huge empires.
At least till I ran into some engine problems. With 40+ cities turns took a long time, had graphic stutters and so on.
Runs better when you play little citystates and not want to create big empires with many towns.

Civ 5 :
Another step into the wrong direction.
It no longer feels like a civilization game to me, only small citystates. Hexfields are not bad but the one unit per tile.... Fubar! And the traits system was nothing for me. Bad AI that cannot use the "new" 1 unit per tile system. AI tries to move Longrange units together with some close combat units and fails hard. Watched the AI one time more than 20 turns when the AI tried to move many units through a bottle neck.

From my point of view :

Civ 2 and Call to Power 2 are the best ones.
Followed by a modded Civ 4 Version with all addons.
Civ 1 , Call to Power 1, Civ 3 or Civ 5, just forget them.
Civ 6, I will not even touch it with a long stick.

PSST.
What about SMAC/SMAX?

Oh i forgot Sid M. Alpha Centauri

Shame on me.

SMAC is a great too.

The factions I like most are the UN Peacekeepers and the University.
The downside of SMAC was to me , that I could to easily abuse the terrain.
Enemy City in the East, just build a high mountain in the west so that the east city got no rain, and began to starve.

So it should be Civ2, Call to Power 2 and SMAC.
All of them are great and have only very few weak points.

Now followed by a modded Civ 4 with all addons.

You are punished for building many cities too early (before your economy is ready to sustain them). Civ4 favors huge empires, but you need to prepare for them. That is the greatness of the city maintenance system: each city is initially an investment, and you need to keep developing your economy to sustain the initial losses (in maintenance cost), but once you turn the losses into net benefit the city becomes productive.

The expansions added the very harsh colonial maintenance penalty (costs for cities in other continents grow a lot higher so you eventually "should" liberate them as a vassal). However, if you play without vassals the colonial modifier is gone.

Maybe you should play higher difficulty settings instead of just the lowest one?

Personally, I heavily prefer Civilization III over IV (I even dropped the series and switched to Europa Universalis because it wasn't enjoyable). People complaining about strategic resources omit that you can simply trade for them. Also, city placement is key, so you always want to make sure that you get those and/or luxuries to keep your population more happy.

I don't hierarchize between 3 and 4. I tend to alternate between them, when I re-launch a Civ game. Or, more accurately, play a game of both when I'm in a Civ phase.

Well, the problem isn't that you have to use settlers for it, it's that you have to do it manually. In Civ IV the mechanics aren't really different (having two different units for building cities and improvements isn't that much of a change), they just introduced lots of automation to this process.

Ironically what you're describing is the exact opposite of how I perceived Civ 1 compared to Civ IV. Maybe I'm playing Civ IV wrong but Civ IV's automation resulted in far more turns during which I have literally nothing to do. Just hitting the turn button and waiting for something to happen. In Civ 1 having to do these things manually IS tiresome but at least they gave me something to do almost every turn. This stretches out turns in Civ 1 but it reduces periods during which I only wait for stuff to happen which I find frustrating.

Not that I'm defending Civ 1's UI but having something to do at (almost) all times was an interesting side effect. Also, frankly in my opinion improvements should be built by cities themselves, not units. Not sure how it's in Civ 5 and 6.

I'll break it down by my own personal preference, just based on ease of use and modern UI amenities.

Civ II

Probably a nostalgia choice. The music is a bit archaic by today's standards and especially modern Civ standards in particular, but that's really the only major downside, aside from getting a copy to work under modern OS'. The game itself is fairly straightforward. Manage your settlements into cities, build wonders for bonuses, amass a great army to conquer your rivals, ally with them, or simply become such a massive technological powerhouse that you beat everyone to space. Of particular note is a few annoying things like late game spy spam from the AI, a few cheaty things and of course, a UI circa Windows 3.11/95 era. I enjoyed getting a pimpin' palace and of course, who could forget the advisory council?

Civ 4

I feel like this is that last pure Civ that Firaxis didn't attempt to really mainstream into a boring mess. It was the first version to really embracing the modding scene, felt complete and felt like it handled everything I hated about 3 in a far better way, or outright removed bad mechanics from that game. It also has the Colonization pack for those of you who are interested. (Although, I still prefer Freecol or the original, despite its age.) I feel this is probably one of the better modern iterations and is worth a purchase, especially if it's on sale.

Civ 5

I actually really enjoyed this, after patching and all DLCs were put into one package. I've probably logged hundreds of hours into great and unique mods, both for adding new factions, or total conversion mods like the Lord of the Rings versions. The modding scene is probably what really makes this game stand out for me, personally. There's everything from Fallout mods and maps for them, the inclusion of all or most of the factions, (BoS, Legion, NCR, Enclave, New Vegas, etc.) They come with unique abilities and units. There's an elder scrolls mod that includes a full map of Tamriel, with most of the factions and races, a Game of Thrones mod with all the houses and a custom Westeros map, along with total conversion mods that completely change the mechanics and maps. As for the core game itself? Yes, it has annoying things like one unit per hex, causing massive movement spam when you're on the march, there were the early nuke 'em Ghandi bugs, and a few other annoying aspects, all of which can be modded out or modified, should you wish. City building felt rewarding and fun, but I will say this, where the game ultimately falls short? The AI. It doesn't matter how benevolent you are, once you've gained a massive disparity in power against the other civs? They start slandering you, become aggressive, demanding and ultimately leads you to simply conquering them out of irritation. There's a good variety of Civs here after DLC, with some being more OP in aspects than others. (Babylon tech rush?) I'd recommend on sale, in a complete package. The still active mod scene alone is more than worth it, imo.

Civ 6

One thing I will warn. It does have Red Shell, and I can't remember if they pledged to remove it or not. If that is a deal breaker for you, simple ignore this entire portion of my post. I can't blame you.

That said, there's good and bad here. The art change is a bit jarring, but the tech trees, unique way of building cities that are each their own style based on your needs is a nice upgrade. The 3 (or 4, depending on wonders) use worker unit limit is actually a good way to remove wasted time between turns watching swarms of workers move about on their automated duties. (Some may feel this is a negative, as the worker swarms can give a deeper feeling of a massive empire constantly building, upgrading, etc.) I personally don't have a strong feeling either way. Spies are handled differently, and units actually upgrade in newer and unique ways, aside from stats changes, unlocking unit specific abilities like bonuses to ranged, bonuses against ranged, bonuses when sieging, attacking not costing movement, etc. There's a large diversity of civs here, each with their own unique way of improvement and expansion. The modding scene hasn't quite caught up to 5's and with the huge backlash over the Red Shell issue, it may not. It's tough to say. If that doesn't bother you, I wouldn't recommend a full price purchase, but a playthrough if you can get it complete and on sale might be worth it.

Civ 1

I rank it here simply because of its status as progenitor and historical curiosity. Frankly, it's borderline unplayable by modern standards. Even MoM's ancient UI is still serviceable and easy to eventually get the hang of, as well as being easier to understand mechanically. Without documentation, the UI is way too antediluvian to put up with, and the same goes for the mechanics. I mean, it might be worth a pick up during deep discount just for collection's sake, but I can't recommend the game itself, unless you're a masochist.

Civ 3

Hated it. Hated almost absolutely everything about it. I hated the cheating AI, I hated the penalties for expanding your empire, I hated the shitty way it handled strategic resources, (which 4,5 and 6 do a much better job of managing.) It just was not fun for me. If a game starts to feel like work or a chore, it's no longer game, or at least, it's no longer entertainment, which is why I play games. I would recommend a solid avoid.

I think both are still very playable today. If you have time for both then I'd start with 3. Civ 4 is the better game mechanically I feel, but Civ 3 is not without its charm. It's got its own unique atmosphere (with some kickass music) and it's 2D graphics have arguably aged better. The only real criticisms I have against 3 is that resource distribution can sometimes be a bit unfair, and the city view, while cool, doesn't really do a good job of reflecting large city sizes.

Apart from graphics (perhaps) civ 4 clearly improves on civ 4 on all fronts except for three
- no city view :( - (weirdly none of the civ games surpassed the original in this regard)
- no palace view :( - (somehow not even civ 3 did this as well as the original)
- artillery units cannot bombard and damage units. Bombarding only reduces defense/fortification bonuses iirc. If you want to directly damage a unit with artillery in 4 you have to move to attack with your artillery unit, which essentially means sacrificing it.

Civ 5 was a move in the right direction I think, but they went too far. I think my ideal civ game would be somewhere between civ 4 and 5.

I don't think I was playing the lowest difficulty setting, but I don't see how that gels - if the AI is cheating for resources and not managing its cities on the lowest difficulty, why would it be managing them and not cheating on higher ones?

The AI doesn't cheat for resources (only money at best), it trades with other AI. You also see often enough that they lack resources for specific things. It does manage its cities on lower difficulty settings, it just doesn't really build any buildings there (on the lowest one at least) which is the reason why the lower ones are easy to beat (apart from some other stuff).