As recommended by Jaime Griesemer

I was going to recommend Fire Emblem before I even read the end of your post. I've been a fan since I was a small child. The genre's not for everybody, but if you like staring at your screen for long periods of time doing nothing but agonized thinking, it can't be beat.

I also started The Legend of Zelda: A Link Between Worlds for the first time, and I can't put it down. It's a magnificent game, and it's a wonderful sequel to A Link to the Past.

It's definitely the best handheld Zelda game. It's absolutely wonderful in ever way. And I want to play it again, now, so thanks for that!

I'm in the middle of a Fire Emblem Fates: Birthright play session. Awakening (the previous Fire Emblem from a few years ago, and the one that really made the series more mainstream and accessible) was my first Fire Emblem game and I loved it, despite never quite finishing it.

Birthright is very similar to that game in terms of accessibility (although some things are still confusing and not well explained--the Seal system, for instance). I'm enjoying it a quite a bit, but my plans to finish it and move on to the Conquest version immediately have fizzled. I definitely will not be able to play both of them back to back, and at this point I'm betting that I'll skip the third story line in Revelations altogether.

Stardew Valley (not a handheld game) has taken time away from my Fire Emblem session at the moment, and I'm not sure when that urge will go away. It's such a good, relaxing, charming game that I really find myself gravitating to it at the end of the day to unwind, and "just one more day" turns into three, and then four, and then ten, and before I know it, it's 2am and I have to force myself to quit.