For ugliest, I think that Waruvile and Waruvial got hit pretty hard.
Yikes. Yellow stripes against dark brown scales and a white belly make for an atrocious clash of colours. Not only that, but the latter's 'glasses' and beady eyes make this hardcore gangster gavial look like a senile old kook.
For coolest? The gleaming, golden glory that is 24 carat Probopass.