There are no new attacks planned at the moment, I'm afraid!
Hip attacks and butt slams wouldn't be on my personal list either, to be honest—I'd see them more as adding flavor than providing anything new, in terms of gameplay.
I think VRMs support custom animations; so if that's something I worked out I could add mod tools for people to add their own attack moves... but that might be a lot more work than it'd be worth, probably!