I think this function is very useful, me and other animators at our studio using it a lot and I think this feature is kinda underlooked. I would love to have an ability to create layers with a scale multiplier while retaining the same functionality as standard 1x layers (i.e. drawing, transforming, etc.). It helps tremendously for rough animations especially when you’re using graphic tablet since higher resolutions often easier when it comes to sketching.
Currently it’s possible to create reference animations beforehand, but as soon as you exporting them to the reference layer, they’re pretty much set in stone. So yeah, some flexibility would be really nice to have.