Sorry for the late response, it seems like you are really on top of things! Seeing such responsiveness from a dev about accessibility is very nice.
You've already mentioned a couple of things that are worth looking into, but another one is to make sure that their are no visual only puzzles. I.E you can't finish it if you can't see it.
Aside from that though, it seems like you already have your head and heart in the right place on this matter, so thanks for being a good example to others! :)