Actually, with hair spray and good amount of gel, I can almost every male character's hair style. Axel, Riku, Leon, Sephiroth, Xaldin, Xigbar, Xehanort, Ansem, and the really-longed haired characters excluded.
I can do Roxas, Sora, Cloud, and the spikey-haired ones though. As of now, I'm growing my hair now, so I'll have even more spikey hair than them (If spiked) xD
So, the hair style I want... Probably Riku's or Xehanort's style.