One thing I personally value in something like this is the ability to opt in or out of features, so that I could use it a fairly low level set of utilities (think large user-facing piece) but also as a full-blown opinionated UI library with lots of things ready to go (think internal piece).
I think I can check this one off by introducing modularity. The way I see it is that you have a download page where you can check all the features you want your kit to consist of and get just that.
