I'm the most upset about what they did to Girafarig. I always really, really disliked Girafarig's design, and it turns out that has mostly to do with the stupid, fugly, and stupid little "Chain Chomp" head it has on it's tail. If it had heads on either end of it's body and the Dark type like here, then it'd be one of my favourites (and I could really use some favourites in Gen 2...).
The one one that hurts me the second-most after Girafarig is Noctowl. Noctowl is another pokemon I always really disliked, because it's just an Anime Owl, turns out it could have been something better.
With some of these designs it almost really seems like they went "Yeah it looks alright, but can you make it look 30% blander and 20% more boring?"
Yea it looks pretty neat (the Noctowl design). But I'm wondering if they might have cut it since it kind of resembles the Pidgey line a bit.