Hmm, well, to add on to Azaroth's feedback, I feel like he should be a little mightier. 1-2 Might is your bog-standard guy, and Shotaro sounds like he's pretty stronk - so I would have guessed he would be about 4 on the might scale. That's kinda of an opinionated thing judged by the backstory and appearance though, if it messes with the planned statbuild of your character then pay no attention xD.
His skillset looks pretty good and balanced out. I like the idea of trading his energy/metabolism for boosts of power. Sounds like it would be cool for a 'final stand' kind of scene, where he basically sacrifices his life to become Chuck Norris to the power of Bruce Lee in his final fight.
Not much other thoughts other than I like his concept; I'm probably going to be disarmed of my battleaxe more than a few times if Halberd ever ends up fighting this guy.