Just to confirm, uBO can do the same things, mostly (and I've switched to it myself), but the UI is not on the same level when trying to block css / images / scripts separately. uMatrix really is an incredible UI achievement.
Fishy things get painted red, hopefully good things get painted green - reload and try again, if it didn't work.
I sure hope, some maintainers pop up and keep this thing alive!
That's an enormous amount of work (for someone totally unfamiliar with the codebase that would have to learn) to undertake on the off chance that it would be accepted.