I may have one comment concerning the clone/copy/singlepath:

First of all, I think (and I hope everybody agrees) that it's necessary that the used brush could be any item, not only a single path.
(The same than the clone tool works, you can clone any item: path, shape, group, text...)

So this raises the issue of the "single path" mode, how can this be handled if the brush is a group of shapes ?

Steren