Final Fantasy 5 Advance to me...6 was always to me kind of overrated and trashy. The game up to when the world was blown to bits was great, but the other 1/2 outright ruined the quality of the title. The last part was a lot of optional things, thin story, disjointed, a lot of collection. But, the killer was the hosed leveling/magic skill earning system because essentially anyone could use the best weapon/armor in the game and could back it up with a Ultima laiden death throw from each team member laying it on thick making boss fights as scary as a pack of IMPS in the first 5min of actual gameplay.
FF5 was hard as hell, ported quite nicely too regardless, and the system just worked because even if you could give everyone everything in skills (not gear), but not having a diverse party you were screwed.