"...the fact that you can modify content using a simple text editor."

And that is what D|S has already broken.
Try editing a .ds file. You can't, unless you let Studio translate it back into cr2 format.
Problem is, D|S can't properly read cr2 files, that's why the MorphBrush doesn't work with it, so any translation will be not as good as the original Poser cr2 file.

Weightmapping would also break each and any existing  Poser content, unless you find a way to convert  all Poser rigging PERFECTLY into weightmapping.
And so far I haven't seen such an app that could do it.

And even IF you get a perfect weightmap for a former Poser mesh, will it be as easily editable as Poser joints are, or will it lock away joint editing to a few elite professionals, like V4 already did with her inane UV-mapping that can only be used with by those who can afford a proper 3d painting program ?