When working with the library, it can get cluttered very quickly. One piece of clothing can easily have 5-15 colour variations. Moving these variations to a second tab, would make it a lot faster to scroll through, and find what you want. Having an option to stack / unstack the library would make it usable as before for people prefering to have it all in one place.

Autodesk Character Creator got this already, and it makes the library a lot neater. I've made a post previously with the idea to make "prefabs" of models and textures, while having a dropdown of textures to choose from in the slots. I'll add those as pictures as well.