Usually the fastest, strongest, or otherwise most competitively pokemon are the cool, edgy, dark, powerful looking pokemon.

But what about the cute pokemon, the pretty pokemon, the elegant and beautiful?

Mega Gardevoir is the only thing that immediately comes to mind as something that can compete, and only if she's set up properly.

What else is there, either in stats or because of their abilities and movepool?

Please, no suicide bombers. Almost every pokemon can be guaranteed their first turn with the focus sash and you could certainly use a slow and weak pokemon and use Destiny Bond, but I'm more interested in pokemon that actually stand their ground.