I really love HoMM 2 design, it's the most fairytale like game in turn based genre of games for me.

Price of Loyalty expansion campaign is much more challenging than HoMM 3 The Restoration of Erathia and Armageddon's Blade, but maybe it's way easier than Shadow of Death. I also love the music with optional opera singing.
https://www.youtube.com/watch?v=YcNeOxJs31Y

As for battle system I find it more comforting to have a squad of archers than in HoMM 3, I also like zipping lighting bolts here and there ;)

HoMM 1 was the first game after King's Bounty I tried and I loved it to death. Then came the second game and I loved it even more. Sometime after when HoMM 3 was released and I saw the main menu of I just knew that it would be even better and it was for many years. But after years of oblivion when I finally decided to complete the whole series I realized how good HoMM 2 really is. Don't know the real reason, call it magic ;)

Now I'm to finish the HoMM 3 Shadow of Death expansion, it's nice, it's really hard, it's good looking but it's nothing in comparison of HoMM 2. I hope you'll understand what I mean in due time.

I'm currently playing Pathologic Classic HD and the next title from my backlog is Divine Divinity.

Limbo.

I actually don't know yet because I decide what to play only after I finish the current game. Even the genre is undetermined because I tend to play pretty much all of them.

I have multiple games I say are "in progress" already, so in theory I just need to actively put emphasis into that. But probably one of

Stardew Valley
Dragon Cliff
Diablo II (just base game, not LOD)
Darkstone

Or if I'm dipping back to games that have fallen off the active list and probably need restarting from scratch:
Psychonauts
Witcher III (base game)
Metro 2033
Dungeon Defenders
Dark Messiah of M&Ms
etc.

With the gift of Obduction from GOG it is next on my list.

Lies! Matters relating to the dreaded "backlog" are anything but simple. ;)

If you need help picking one out to finish completely, I'd say Stardew Valley, partially because I'm playing it myself with a friend and because the developer is adding some new stuff soon as far as I know.

I don't play games one at a time, nor do I deal with my backlog one game at a time. I play a little of this and little of that, with no set plan as to when I'll play what.

Next is, erm, was Fairy Bell.

I ended up going through it in one sitting, which took about 90 minutes.

It SHOULD be The Witcher 3 (got it for XMAS about 2 years ago). I loved and finished the first Witcher. I got HORRIBLY STUCK in the middle of the 2nd Witcher (trying to fight Vinson Traut) and even quit playing TW2 for a solid year because I could never get past him when I tried! But I managed to FINALLY finish him off about a month ago, pretty simply actually, and now I'm on Act III (according to the guide that came with it) and hope to finish it by the end of Summer.

My NEXT game off the backlog is yet-another game I really loved, but ALSO got HORRIBLY STUCK... only this time, due to the game's total inability to save just before you take a giant leap. The game is DOOM (the newer one) and the part I'm stuck on was trying to cross that "bridge" of ductwork (or whatever it is) where you climb up onto it, run and short-jump across spots, hide behind walls, and there are dudes way up high in the "rafters" shooting you with artillery, and then... about midway through, you have to JUMP YOUR ASS OFF to make it across this HUUUUUGE gap that is impossible to jump and the game makes you REPLAY THE ENTIRE GODDAMN BRIDGE every single time you fall, so I just gave up on it!

Well, until I finish TW2. Then I'll give DOOM another chance. And if I make the gap, I'll continue playing until the next horrible sticking spot. And THEN I'll give up on that one.

I have to make a "sidequest" here to mention somthing; I just can't understand how horribly the new/recent "Prey" went off the rails. The save/restore system is fine, it's just... I can't manage to get past all those largish "typhoids" or whatever they're called, and don't EVEN get me started about the NIGHTMARE. I'm stuck in THAT game where you have to "swim" (zero gravity) down the middle of a shaft to recover a harddrive or something similar, and I just can NOT force myself to "get into" the mindset of the CRAP you have to put up with to fight these "nightmares" off. I did it up till this point... but no further. Prey is Dead To Me(tm) now.

I only mention Prey because, like TW2 and DOOM, they are games I previously gave up on and I really hate doing that, and like to eventually go back and finish them. I can't see myself ever touching Prey again. So after I finish TW2, and maybe get further in DOOM, the REAL ANSWER to your question is... assuming you mean a "new" game you haven't played yet... The Witcher 3! :)

I'm currently slowly going through Warcraft 2, after that I've got Borderlands: The Presequel to go through.

Some that are currently being considered:

Serment: Contract with a Devil. I have gotten this game to work on two computers without any issues, and I have "played" through the rather lengthy prologue on one of them (I skipped it on the other), but have yet to start the actual gameplay (aside from brief unsaved excursions to see what it's like). (Note that this is the only game currently on the list that I haven't played in some form before.)

SaGa 3. Noite that which version has not been decided (I've played Final Fantasy Legend 3, and I've played the DS remake in the original Japanese; I haven't played the original Japanese Game Boy version, nor have I tried the DS version's translation patch).

The Guardian Legend: Here because I think I might need a short-ish break from RPGs. My one worry here is that there's one particular boss that is way too difficult for the point in the game which it appears. (For this game, I allow myself to use save states in the room you arrive in after the intro stage, and in any room where you can get a password, in order to avoid having to worry about the password system (unless I decide to cheat to bypass that one boss, which I *have* done).)

No no no, that's NOT how this works. You MUST install the LOD expansion before starting a new Diablo II character. Really: many years ago I tried both experiences (with and without LOD) and the game works at its best only with the expansion...