Hadn't been around to check the forums in a while, so I haven't had the chance to catch up on this thread, but might read through and reply later on!
I'll throw some in the mix for the time being:
Suikoden II (PS1): I've come to appreciate its sequels as much as this one (and really can't decide whether I prefer 2, 3 or 5 best), but I have the strongest emotional attachment to Suikoden II. I love its pseudo-historical setting, the relatively subdued importance of the main character, the regional nature of its conflicts, as well as
the little bits of emotional conflict other games don't have (say, Flik threatening to kill Fitcher in Greenhill to protect him), and the emotional height of the big confrontation with Luca
. I love its little references to Romance of the Three Kingdoms, too!
Europa Universalis IV (PC): I've always liked some strategy games, having grown up with the Koei classics, but EU4 really grabbed me in ways that no other game has. Playing each nation is substantially different, and the freeform nature of picking your own challenge (by picking a nation and tweaking a few parameters) really lends itself well to the genre. Everything is a number, but nothing is pre-ordained. Beats even Civ V's "one more turn" factor, since it trades it for "one more war", "one more mission", and so on. The only game I have ever lost track of time while playing.
Dark Souls (PS3/XB360/PC): Bottled lightning that I think Demon's, Dark 2, and Bloodborne didn't quite match. I'm sure others have elaborated.
Der Langrisser (SNES): Not a particularly amazing game (the first in the series is tighter although DL is more polished), but the various routes and characters, particularly the Independent route, really separate it from most fantasy games while the gameplay hits a good balance between strategy and RPG. Not as tedious as tactical RPGs, but still has a strong character focus.
Mount & Blade: Warband (PC): Lost hundreds of hours to it. A bizarre mix of action, strategy, and RPG that was almost too ambitious. At times a sandbox like Pirates!, at others a trading simulation, but your focus gradually grows until you are able to sustain your own empire (at which point the game starts to break down). Very moddable - with many mods completely changing the game, particularly The Last Days (originally for "base" M&B but inspired many features of Warband).
Space Rangers 2 (PC): Like Mount & Blade, a bizarre mix of genres, but this one mixes Pirates! With a more strategic, turn-based game in a sci-fi world much more in flux. Special missions even introduce text adventure and RTS mini-games. The rapid development of technology makes the task ahead go from "impossible" to "dumb easy", but as it is, still makes for a fun "choose your own adventure" on a grand scale. The sequel even introduces a second pirate conflict in addition to the Dominators. Great music, too!
Opoona (Wii): It's hard to describe exactly what it is I like about this game. It does a fantastic job of atmosphere, with colorful graphics, varied locales, and incredible music (hard to believe the same composer also led up the bland FF12 soundtrack). If I had to say in one word, it's uncomplicated - it can even be controlled by simply the Wii nunchuk (one analog stick, two buttons). I found it at a time where every game seemed too busy and feature-rich, which I know sounds ironic given the last too entries, but it was a refreshing change and I have found myself engrossed in the game multiple times since then, making it a great palate-cleanser. What may be surprising to some is that it's not the cheery kids-tale it appears to be; it's more of a coming-of-age story, and the protagonist himself even fails at times only to be helped by friends.
/edit: forgot one important one!
Destiny of an Emperor (NES): Got me hooked on RPGs for real (Dragon Warrior 3 was good, but not
this good), created an obsession with Three Kingdoms, and led to one of my biggest passion-projects,
Destiny of an Editor. Despite going off the rails around Yuan Shao, its adaptation of RTK along with a really damn good translation for its time made for one of the better plots for an NES game despite being bare-bones.