Well, they could animate an OVA showcasing the final rounds of the Washizu-Akagi match, but really, I don't mind the ending. It was awesome. It had all the conclusion one needed ...
I'd bet either a short series (11, 12 or 13 episodes) showcasing the final rounds of the Akagi-Washizu match, or a tightly-packed OVA ...
and maybe some yaoi 
EDIT: Please delete any one of the two posts I did. I didn't realize the previous one was really posted, sorry - some problems with my connection at times.
EDIT by Mod: I couldn't figure out which one I should delete, so I combined them instead.