I say yes to armor. Get some Rexlace (RX-100-14 Black) from Michaels and some styrene and make some removeable armor. Looks good either way, he has that high tech ninja feel to him. Sweet sword too.
Thanks for the help. If I add armor, I think I'm going to stick to greenstuff and maybe some vinyl plastic sheeting I've been using. I've done the removeable armor before and it never looked right.