Wild Arms for me. Loved that game on PS1, but now, the battles are just awful. They feel incredibly dated.
I, like many of you I'm sure, used to spend countless hours, months, even years playing games which I considered my favorites, but now for whatever reasons I just can't actually get through them anymore. Here's a few;
Final Fantasy 8, 7, 10 - 8 is my all time favorite game, and also the first FF that I ever played. 7 and 10 are close. Nothing has since been able to live up to the emotional value that these games made me feel, but sadly they just doesn't make me feel that way anymore. It's not like I don't have the time or energy, but it's like now I play them they're just slow. I panned 13's auto-battle feature when I first played it, but now I kind of appreciate it, storywise though it has nothin' on those 3.
All Devil May Cry games - Absolutely hated 2 and 4, but did spend a lot of hours playing both of them. 3 is my favourite, but 1 was great too, there's nothin' wrong with them but just can't get myself to bother with these goddamn half-assed puzzles anymore, I know all games are repetitive but DMC games feel much more repetitive than others, which is a formula that used to be quite ok with me.....
Metal Gear Solid 1 & 2: Just can't bring myself to play them. In 2 there were a lot of bits I didn't like, such as the bits with the IR sensors, and the story almost never goes how you want it to (Just DIE Vamp! DIE!!), but 1 I dunno it's a classic but meh.....
I agree with your picks for FF titles. Those 3 were my favorites too. Like exactly those 3. I'd probably rank them in order of: 7 > 10 > 8. But still all 3 > every other one. I didn't like 13 though. Got bored about 5% into it. Gave up for months, pushed through to about 20%, gave up again since got bored. Snowe was the only thing really keeping me interested at all. One of the better FF characters imo.
I also agree about MGS1 being a great game, but really hard to go back to now. It's just a lot worse. . .though they did remake it on the MGS2 engine.
Speaking of which, if you need an excuse to go back and play MGS2. . .get MGS2 Substance. It had a FUCKTON of VR missions. They're fun too, and some are really elaborate and challenging. There's also challenge missions called, "Snake Tales", where there's fake stories where Snake has to go through the Oil Containment Facility and eventually take out a boss like FatMan, on Very Hard mode. It's challenging but fun.