Character models and animations

I thought I didn't like the new character models that I added to my WotLK client until I reverted back to the pixelated vanilla monstrosities (I remembered them much better in my mind from my youthful nostalgic past).

But the new model animations are so bouncy and cartoonish - absolutely out of place.

I see people make all sorts of patches to work with the client. Isn't there a patch for WotLK that sports the new models but with the original animations? If not, is it hard to customize one such?

Apart from that, the general stuff with models - I like Tyrande's classic model, rather than the overdone later models of her. While also, I enjoy Sylvanas' post WotLK less skimpy model version, rather than the previous.

How hard is it to create custom patches for your client, relating to choosing models and animations to work with it?