After experimenting with the eraser tool a little bit, I think the best answer to my use case would be to expand the tool to three modes, something like:

- Delete - Erase from selected - Erase from all [i.e. all on current layer]

Additionally, the tool needs the ability to "reach into" groups when erase. Currently it just leaves the erasure path behind without doing anything if you try to erase a group with paths inside.

Also, the dynamic stroke features aren't very useful for erasure, which benefits most from a uniform, controllable shape.

-mental