I like some of FFX-2's music, Luca for example, but in general I was disappointed with the changes, especially to the battle music. I think FFVIII's soundtrack has more outstanding/memorable songs than FFVII's, but FFIX is my favourite by far. Maybe it's just the whole style of it that I like, things like "Sleepless City Treno" and "Protecting my Devotion". I want another FF game with music like that.

And I'm one of the probable few that would like to see more "Otherworld" type tracks in the games, especially for boss battles