I don't think there is a client that will let me connect to 9front from Android, is there?

I see what you mean in this and the other comment. With 9front, you rely less on issuing commands to remote machines because you can directly access their resources. It's worth keeping in mind when comparing Plan 9 and Unix from a Unix user's perspective.

Being able to pick large fonts on the server isn't the same as leaving the fonts up to the client. When I use terminal emulators, SSH, and tmux, I can switch between different clients with different resolution, pixel density, and screen orientation and have the text display acceptably on each (minus text reflow for history, which is an issue).

> I consider the Sam regular expresions far more powerful than the vi keys themselves.

I agree, structural regular expressions seem like a better version of vi commands. It was reasonably easy to make some complex edits in https://github.com/martanne/vis when I tried it, and it felt like I'd only scratched the surface. I could see myself still using vis if it had tabs like Vim. (Tabs are a stated non-goal for vis.)