The trio trained by Master Eraqus have made an iconic impact upon the Kingdom Hearts series not just because of their importance to the overall plot, but, for the fact that they were well received characters in their own right. 

 

So, that made me wonder, seeing as Ventus, Terra and Aqua have had as much development as Riku and even more than Kairi, would Tetsuya Nomura be kind enough to place them into new costumes once they've been revived? I personally hope so.

Probably so. I always wonder if Terra wear non-armor clothes.

 

Terra is an unusual character. He's been possessed by Xehanort as Terranort, so, it's just a question of Terra returning as a whole being. If he does then he'll get a new costume too!