In my opinion the combat has improved of the course of the three games but the all important story has become somewhat of an embarrassment at this point.
Here are some of my main concerns:
1. Fighting is meaningless: You no longer level up by fighting. All XP is gained from finishing quests (Mostly fetch quests). I did a lot of enemy bypassing in the original and expect to do so again now that I actually don't NEED to fight.
2. MMO feel: Pretty much the consensus of the game-play. Which is cool if it had ONLINE features but nobody wants to play a MMO offline.
3. Too much emphasis on outfits: FF X-2 all over again? Give me a leveling system and crafting over changing skank-wear.
4. Lightning is even more unlikable: She and most of the cast are losing their personalty after living hundreds of years. Unfortunately we are stuck with 1 playable character that never had much of one in the first place.
5. Poor storytelling: Obviously a big problem for this series and "The Return" is apparently even less coherent then XIII-2. Plus now I have to scramble for time just to keep it going?
I'll update this once I get my hands on a copy tomorrow.