Hi
I love the Default 6 theme and the Theme Adjuster is a superb addition.
I created my own mod of the Default 5 theme a while ago with replacement icons for the entire set including midi (plus my own toolbar icons). I've just reworked them to fit with the Default 6 colour scheme.
I've followed the Default 6 highlighting for mouse over and select but feel this could be a bit more prominent. The icons themselves are all derived from The Noun Project (
https://thenounproject.com/). It's a work in progress and, ultimately, could just be for my own use. That said, I'd be very happy to share them! Please let me know what you think.