Currently playing through this for the first time, at Ipsen castle so near the end of disc 3. It's really quite a game. Absolutely gorgeous in places. The last FF to have 2d backgrounds, they went all-out, and it shows. Ofc music is incredible as well.
My only criticisms: It's a bit linear for my tastes. There is a lot of dialog and forced "Now you control X characters" swapping. Plus the story while on the whole being very cool kind of looses its steam at points. Disc 3 feels like the wheels are starting to spin and even though I'm nearing the end it doesn't have that build-up or dread that FFVI or FFVII had.
Rn I'd rank it above FFX, where I enjoyed the combat more but IX doesn't have anything as bad as blitzball or the temple puzzles. The card game is actually a lot of fun!