My favorite: Braviary. Doesn't matter that there's already a gajillion bird Pokemon. Braviary is just so awesome. And he's based off an eagle. 'Murica! >:3
Least Favorite: Now the list for this is expansive... But if I have to choose just one; Vanillite. I despise it. And its evolutions are even more unoriginal... Let's take an ice cream cone and add a scoop... TA-DA! Evolved form! ......No.