I'm 6'4" and paddle a Nomad 8.5 as well- plenty of room for bigger feet and longer legs. I'm quite a bit lighter than you, & I don't think there's a problem with 'too much' volume. And it's truly a great creekboat (no, I don't work for Dagger) - I believe the design alone has given me a confidence boost from prior creekers I've owned. But to Doug's point, it's not a true planing hull so if that's your gig, maybe the Burn is a better way to go. I've also heard that big dude have been drooling about the Mega, so that's probably worth a test drive.
Take up Hobie on his offer for a demo...