Yeah. the costumes were really well done. Even the swimsuit. Sure it's total fanservice, but I was quite surprised at how detailed and original the design was. Usually when they do suimsuits (Xenoblade and Xenosaga, I'm looking at you), they just try to get away with giving the ladies the least amount of coverage possible, but the designs are completely boring and unattractive. Serah's swimsuit costume looked like it was probably designed by someone not simply fishing for quick eye candy (woman or gay man maybe... or maybe a really thoughtful straight guy). The summoner costume was a bit unfortunate though, it looked kinda boxy, somehow. They made it look attractive in the prerendered graphic with Serah jumping through the air, but when she was just walking around, it looked like an abrupt triangle.
I'm actually a really big fan of Serah's default outfit, though. I think they really captured the same basic theme as Lightning's outfit (FFXIII), but made it more feminine and less militant. The only outfit in the series that I completely dispise is Serah's original outfit. It looks like a fluffy nightgown. It's impossible to take it seriously, and to really believe someone would walk around town (or a night carnival) in that gidup.
Not sure about Noel's Aladin pants though. He really looks like a Kingdom Hearts character with that thing.
On other things, I'm not sure I understand all the Caius love. Yeah, he looked/sounded cool, but in the end, his motives were just rediculous. I tried explaining the plot to my girlfriend, who was interested in the series, and everything in the game sounded alright until I tried to explain WHY the villain was doing all this, then I felt really stupid for even trying to explain it. I think he possibly has the single worst motive of any villain in the FF series, possibly even worse than Seymour. I was REALLY let down when he finally revealed his reasons. They could have come up with something far less silly.