How about a Prior All Mountain Freestyle?
All Mountain Freestyle Snowboard Model From Prior Snowboards | Buy Snowboards Online | Whistler Canada
The 156 is suitable for your *girth* lol
although after going from a 153 to a 159, I don't think I'd ever go back. I'm only 160 pounds but looking at a 163 for true freeriding...
Plus prior handmakes everything so if you want increased stiffness to compensate for weight in a shorter board, they can do that.