I think it's more the raptor's arms than the muzzle that are the problem--the muzzle seems simple but effective. Raptors have those tiny little arms/hands, remember, and since you've drawn them longer than expected they make the rest of the raptor look off. Not that I could do any better, but of course you already know that. :P

Also should the dragon's tail really be allowed to curl up and into the way of the driver's vision like that? One would think the tail would have something binding it to the dragon's hindquarters or the harness frame to keep it out of the way.

Good job on this, though, aside from my little nitpicks. :)

Lol, all true points, the main problem on the tail is that it's really too long to effectivly tie it anywhere, haha, and your probably right on the raptor for the arms, awh well, it's what happens when I try to copy from a refrence, I learn the anatomy, but I don't copy it all that well in terms of the length or hight of certain things.