I'm actually playing through this right now, and so far:
PROS:
-Amazing addition to Tales combat system, really well-though-out.
-The overlimit gauge.
-Interesting plot elements.
-Luke's journal: I LOVE being able to put the game down for a while, come back, and know exactly where I left off.
CONS:
-Weak, stereotypical characters.
-Weak overall plot. Too much macguffin-chasing going on.
-Graphics are low-quality and poorly animated outside of combat, which is unacceptable for a game that came out toward the end of its generation.
-Soundtrack is nowhere near the standards I hold for Tales games.
-The overworld map is horrific.
-No voice-acting in skits... why the HELL are there no voices in the skits!?
Yeah, I listed more cons than pros, but it's still a great game overall, imo.
EDIT:
No set of characters has ever endeared itself to me like the cast of KH.