Good news: buttons and unstyled buttons look great in Themes 3.0 or at least the way they should, also reduced the extraneous CSS that some places did to change icon color of unstyled buttons on hover.

Bad news: themes 3 initialization time is around 1 second, but i'm sure I can optimize it further.

Undetermined news: I'm considering making states essentially "hard-coded" or at least partially. I can't think of many cases where a component might need more than 1 state unless it's an inherently stateful component like Button/Input, all other components so far either have one extra state (text has "faint") or none. It would also help the inheritance between disabled/hover/active/focused.

Oh and also specificity sorting is in place, at least for parents amount.