I made a thing inspired by this thread and the solo artist challenge:
https://wiki.project1999.com/Feats_of_Strength
Basically it's solo artist challenge without the contentious ranking system and with (what I think) is a much more visually appealing layout. You can tell at a glance which classes have killed which boss and what they used to do it.
It's a work in progress and I'm sure there's bosses that should be there that aren't, and bosses that are there that shouldn't be. There's also no existing kills added to it yet. I'm also not an expert or anything so maybe I missed something major.
Hope some people end up using it eventually