literally just saw this post but I routed and did this. I hope "all characters" is a good enough route name for it. could it be added as a category?

I'm also working on an "all bosses" route which would be fighting every unique fight including Satan. :P

Yeah I was doing a fraud all achievements route doing 55/58/unhidden achievements/just the ones you can do all in one playthrough. My bad. No need to add it to misc even because I'm going to do all characters and all bosses categories instead.

I do want to do an all achievement run at some point though playing through the game once on pain one arm, once on normal joyless both arms all characters, and reload an earlier save to do another run with no arms joyful or something like that.

https://docs.google.com/document/d/1LfpzRy94Dx7vTPmDKpSc0zBXvlC2NOKgtEIfFagYb28/edit

The guide pretty much says it all. If you're crazy enough to go through 14 rounds of roulette with 8 characters this run is for you. :)

I am officially happy with the route. Might not be absolutely the fastest way but it's good.