Another game I have to mention here just because it is within eyeshot is
Final Fantasy Tactics Advance on the Gameboy Advance. I was expecting just a GBA port of Final Fantasy Tactics on the original PlayStation. But I was pleasantly surprised.
The job system and overall gameplay mechanics were greatly expanded and improved upon. You could spend over 100 hours on the game! The story as well is great, but it's rare that you find a JRPG with such fun quest and battle mechanics that make the random battles something you look forward to, rather than dread.