I think an AWD F56 would be terrific, especially here in the Northeast US where we have harsh winters. Subarus and Audis are all over the place and the Mini does not have a great reputation for winter traction. Unfortunately I doubt that it would ever happen - too much technology to squeeze into a "mini" body.
As I've read over the past few months at various sites, the F56, as well as the 4 door F55 due out this fall, will NOT be available as an AWD. But the new F54 Clubman due out the 2nd half of next year WILL have AWD as an option.