You could get into Dragon Quest games, if you want old school JRPGs. Complexity might be a bit lacking given the era, but doing the old NES ones without a guide is excruciatingly difficult and you can lump on RetroAchevements to add more pain. RA generally adds additional challenges to any older game so you have to play a little min maxing to accomplish them.
I mostly thought of it since RA is beta testing multi sets with DQ9 and getting every accolade might be one of the most insane things I could ever suggest.
I was 1 most of the time, but my advisor was 4 so it worked.
No way I could pull off 3 with my build, I'd look like a super villain.