I first want to say that I agree with the top three results; they are certainly the most blatant offenders.
I also echo what many have said: the new models are pretty great, but it's mostly the colours being off that disappoints--and the new colour schemes aren't even bad in many cases, they just aren't what we've come to love.
I'm no pro at describing colours but I'll give it a shot.
One of my votes was for the indigo crab. While I love the nice, dark colour, one thing I loved about the crab models is their distinctly white/pale undersides. The top of the body is also missing that almost grey-ish pink(?) tone down the middle. The shade of blue itself is a bit off, as the old model has some teal(?) to it, in addition to the darker blue. My suggestion would be to keep the nice, dark model they've made and maybe throw in one more that looks more like the original (pale belly, more teal to it, lighter details on top). As an aside, I wouldn't mind seeing a second vermilion crab variant with a paler underside. I'll still tame the crap out of the new crabs even without changes because they are cute af.
My second vote was for the brown bone spider. While, as mentioned by Veph in another thread, I like that the spiders have actual spider anatomy, the bone spider update is a bit devastating for me. The brown and the green-grey feel like the worst to me. I loved the brown because of the rich brown colour it had, and how the spikes and other features were much lighter. I loved that the undersides to its legs were a noticeable greyish purple. The green-grey I loved because of the much cooler (read: more blue-ish silver) grey tone it had for its body and bones, and the purple webs. I loved how extremely dark its dark areas were; the contrast appealed to me. This probably sounds dramatic, but pending how the updated bone spiders look in game, I likely wont keep a single one if they are all forced to look like this.
![Sad :(](./images/smilies/icon_e_sad.gif)
My last vote was for the blue black wind serpent. While I absolutely agree that the white one is all wrong colour-wise (where's the actual white scales and lavender shades in its wings?), the blue black one is a pet that has been with me for some time so my vote was more emotionally driven. Overall, I love this new model. I really do. The only change I'd really suggest for the blue black one is to add in one more variant with a nice, slate-blue belly. Maybe, depending on how it looks in game, this variant could be slightly lighter/have a teeny bit more blue where the black bits are. The updated one is fine colour-wise, and I wouldn't abandon it, but it's just not the same. As another aside, I am going to tame the shit out of this model as well, and hope the artists get creative and add even more variants in. It's really a gorgeous model.