I doubt that Tony Hawk could ever hope to survive an attack by a Russian Motor Rifle battalion, even if he did impress them a little bit with his vert skating.
It's probably impossible to make a realistic skateboard anyway, as the vehicles in OFP only move forwards via acceleration, whereas a skateboard just rolls. and we'd need new anims, which we cannot make, unless you want a guy just standing rigid and not moving. Besides, the damn thing would EXPLODE if you hit a wall, just like the motorbike in Res.
I say we all stick to Tony Hawk's Pro Skater for our skating, and leave all the high-calibre stuff to OFP.