I blow at hard platforming games with complicated fighting systems, myself, but still managed to beat Castlevania: Lords of Shadow on Hard (Knight difficulty was their name for it, I think). Yep, OP should take your advice, just work at it.

This here might be part of the problem. When I first played Star Wars: X-Wing back in the day, I only had an el cheapo low-budget joystick. I had a really difficult time piloting my ship and always seemed to be drifting too far in one direction, overshooting my target or feeling like the stick was too sensitive one minute and not sensitive enough when I needed it to be. Then I got a much higher quality flightstick and... wow, day and night difference, and I had a much easier time.

Yup, might be time for a hardware upgrade. Get a better stick.

Do a barrel roll!

Sorry, couldn't help myself. First thing to keep in mind is that each space sim will behave a bit differently and have specific things you need to pick up to be good at it. That said, there are certainly some tricks that are nearly universal to the genre. Since most space sims will involve quite a bit of dogfighting I'll focus most of my attention there. First off, try to avoid head-to-head passes- while it's tempting because it's easiest to hit an enemy that's flying straight at you it's also easy for them to hit you, and you don't want to engage in a battle of attrition. Take a few shots at long range, then veer off slightly, but keep your enemy in view and as soon as they go past you try to jump on them then ride their six the best you can giving it all you've got. For aiming you need to learn to lead your target, and the ease of doing this varies greatly from game to game- it's one of those specific things I mentioned that you have to relearn to an extent for each game.

When it comes to evading enemies, if an enemy jumps on your six it can actually be useful to decrease your speed a bit (although this usually goes against your instincts in that situation), as this will let you make tighter turns and make it more difficult for your opponent to follow you through your turn if they haven't dropped their speed as well. If the specific game includes afterburners (or something equivalent) then pulsing them to vary your speed can make you very difficult to hit. Combine this with the previous tactic by dropping your speed, making a sharp turn, then hitting the afterburners- this will shake almost any AI opponent. If you're trying to evade multiple opponents at once then it's better to keep your speed high, make lots of turns (as you'll be dealing with fire from multiple vectors), and again pulse your afterburners to vary your speed. Against multiple opponents you also want to thin their numbers as quickly as possible, so it can be worth it to take a bit of shield damage to quickly take out one or two at the beginning of the engagement.

In games that include guided missiles learn what the best attack vectors are to use them. Fire a missile when you're approaching head-on or directly from the side and you're less likely to score a hit; firing one when you're anywhere from their 4 to their 8 is much more likely to score a hit. Most AI's also tend to change behavior when they're trying to evade missiles, and this altered behavior can make them easier to hit with guns- forcing an enemy to evade a missile from one direction and guns from another direction makes it much easier to score a hit as opposed to trying to hit them with just guns or missiles.

There are also plenty of additional things such a shield/energy management, dealing with capital ships, giving orders to wingmen, and the dreaded escort missions, but these things tend to be pretty game-specific, so you just have to practice and figure out the best way to approach these issues in each game.

You know that that which most people identify as a "barrel roll" is actually an "aileron roll", right?
(The things video games teach you ;) What IL-2 Sturmovik called a barrel roll was inconsistent with Star Fox 64, so i had to look it up, and yep, Star Fox was wrong, IL-2 was right)

clicketh

Yeah, I'm quite aware of that. A barrel roll actually is a useful evasive/attack maneuver (although most are actually variants on displacement rolls), while an aileron roll just means you get dizzy while your ass gets shot up.

Yep. To my (relatively limited aviation related) knowledge, the barrel roll is meant to slow you down a bit, in the hope that your opponent overshoots you.
The aileron roll is for air shows.

There are also several maneuvers often called barrel rolls (although actually displacement rolls) that are used by attackers to tighten up their turn radius so that they don't overshoot their targets.

Ah, I was unaware of this. Thanks for the info!

Well, if it's a decent joystick, it will have no dead zone. Thrustmaster T.16000M is only entry level joystick I recommend. Hall sensors, no dead zones.

Back in the day, when I was a pre-teenager, I used Quickshot Skymaster, which is a decent joystick, not great, doesn't even have a fourth axis, but I still had no troubles playing TIE Fighter and Freespace. I think a decent joystick crucial for enjoying space sims. Maybe the joystick is the problem for the OP, but maybe not. But for me, I have never found there to be an especially steep difficulty curve for these games, and it seems the joystick could be the difference.

If you live in Canada, you can get T.16000M for a mere $37 from NCIX, especially if you live near one of the stores (for in-store pick up and avoid shipping costs). I actually only spent $33 for mine, but it seems they have raised the price since I bought it (2 weeks ago).

I recently because interested in space sims again, and, as far as I could tell, my Quickshot Skymaster cannot be plugged into my current computer, so I bought T.16000M just so that I could have a functional joystick, rather than to upgrade because the Skymaster was inadequate.

Yeah I have a Raider Advanced FX lolol ...

Not really, they start out without needing a dead zone, but unless you don't use it very often or are exceedingly gentle you'll find that you need one eventually.

I use a logitech extreme 3d pro, which for about $30 is quite a good deal. It has basically no deadzone and more buttons than I really need. The only annoying thing is the twist grip. Some games do use it, but otherwise it's kind of annoying.

A lot of space sims do use it though, so for them it is excellent. And for flight games, it can be used as a stand-in for pedals.