A lot of the docs pages are still very scattered and incomplete, but those are definitely things that I should add.
Accessibility is definitely important to me, and luckily a lot of it comes naturally because I'm doing things in a very "old school" way like... actually using semantic, hand-written HTML instead of building it as an SPA that outputs unaccessible div-soup.
I've done at least some checking to make sure it's decently accessible, but I know there's a lot more that I can do. I'm hoping to get some people involved that are more familiar with screen-readers and other assistive tech to help me figure out things I need to change. And of course, once it's open-sourced (should be in the next couple of weeks), if people want to help contribute accessibility improvements that would be hugely appreciated.
As for i18n, it's not something I'm planning in the immediate future. Since one of the main goals on the site is keeping up quality, it's necessary for me to be able to understand what's going on in all the groups. However, it's definitely a possibility in the future, and the organization of the groups into a hierarchy some some interesting possibilities for it, where different languages could have their own separate group hierarchy.