Good idea! It would be cool as a crawler, true. Right now the game is basically just a combat demo, but my idea is for the Career mode to be the meat of the game where you can actually progress and have some meaningful gameplay. But if I get the chance I would definitely want to do something outside of an arena, crawler-like or endless side-scrolling action as you mention, with the combat mechanics that are in place now. :)
I have another good idea, what about taunts? Example you press X and your character will shout something like, Come Over Here, and the audience (maybe peasants) will cheer you up or something :D
I don't know how hard it is to program a game, or how long does it take, but it doesn't look simple.
Anyway i believe in you :D take your time, if the full version comes out, I definitely pay for it 👍