Mono is such a moving target, with bugs quickly fixed in the master but not released for months. Would be great to have an ebuild of master for testing.
Basically we used to have mono git ebuilds in the tree but they were unmaintained and were therefore removed. We really should maintain these outside of the tree IMHO.
Yes, I don't plan to include them back in main tree as they are hard to maintain
I repaired 9999 ebuild and put it into dotnet overlay.