I have crossplayed once as Roxas before. It was fun too because the jacket was heavy enough to cover up the fact that I have boobs. XDDD I wanted to crossplay Roxas during Saboten 2009 because I had my Axel plushie. I love AkuRoku and everyone actually thought it was cute.
But as far as what I would like to crossplay as:
Lelouch from Code Geass
Aidou from Vampire Knight
Wonderwiess from Bleach (He is said to be autistic and well.. I'm autistic soooo)
I'm not really sure who else. The hardest part would be dealing with the... bosom issue. I don't want to use the ace bandage approach or do anything to hold them down because of sensory issues and such.