Looking at it when next to past megas, it doesn't really feel out of place.
I know people say it's a bit too simplistic, and I do get that, but we've had other "simple" Mega designs in the past that, at least I'd say, work out well. (ex. Kangaskhan & Sableye, hell I'll even say Venusaur).
Also, I like that it regains the wings on its head and the gem on its tail from Dragonair.