I think the soundtrack should be rock and metal, since the game has you beating up an army of stuff. As a matter of fact, ditch the game, learn 3D, and make a Musou game. Playing Dynasty Warriors music over this game is a whole new experience.
In all seriousness though, I think there's more that can be done to this game. Musou, maybe, or rts. Maybe a hard mode where you have health? It's fine, tho. (I still want a rock soundtrack, tho.)
Also, I like activating gas, shoving cake in her mouth, then pressing her stomach. There should be some kinda bonus for that. Like a green blush or a longer burp. Not that I enjoy burps, but it's nice torturing dragons.