Hydreigon: Killer battling stats, previous generations has other Pokemon with multiple heads,
but Hydreigon is different. It's looks: dubious, menacing, eerie -- a Pokemon to be fear at.
Volcarona: Enigmatic yet gives of a warm feeling like the sun.
Whimsicott: Cheerful and prankster, looks like a little tree fairy. Who wouldn't love this adorable Pokemon?
Braviary: Both shiny and normal form colors are one of the greatest combinations.
Moreover if one's going to pick a region symbol of Unova, Braviary would be the best choice to represent the region.