I posted in a separate thread but I guess is more proper place for it:
I know that Paper2D currently has concept of a flipbook which lets you create an animation from key frames, but I think is too limited in some cases.
What I’m instead is proposing an animation system where each frame is created by placing various sprites into frame. You would be able to set location, scale, rotation, and color of each placed sprite in frame.
would allow a much more diverse range of animations to be created from existing sprites rather than creating new ones. It would also be able to achieve same type of animation as existing flipbook system.
Additionally, I think it would be desirable to be able to override sprite used for a particular animation instance at runtime. Why? As a matter of customization. Think about a 2D RPG. You could replace various parts of a character like head or body depending on what you’re wearing with override functionality.