I think you'ld be better off getting a skiff at that point, cause it's what your going to have.

I don't have the engineering experiance on catamarans to give a definate answer, but I'm sure Bill can. IMHO, you'ld pull the chainplates or shroud ends right out of the boat for starters. An ARC21 rig is pretty darn powerful !
I14 or 49er is in your future

Or if I were you, I'd sell the mono-slug and get a cat. Just having fun with you, I like leaners too.