While I agree that I'd prefer it not to simply be a Mazda 6 Coupe, the fact remains that I can't see Mazda launching another dedicated platform. So, either a coupe based on a FWD model (likely the 6) or an MX-5 coupe. It looks too big to be the latter, so the former is more likely.
Trust me, I hope I'm wrong!
If it is a Mazda 6 based coupe, perhaps also including the AWD system that the Japanese model is available with would make it more palatable to the enthusiast.