So, I've looked at lem. Lem seems to be a really great start and push in the right direction.
I work in LEM for my personal projects, that dont have other LSP integration needs and hooks into my org-mode/org-babel workflow. These should not be show stoppers, but will eventually be a non issue.
There are however some features that I'm missing in LEM before I can fully switch over.
1. The documentation for Lem is lacking.
2. I have lazy hands and hit shift on some keys when I shouldn't (shift and backspace for example). I'd need some way to ignore that.
3. An built in undo, (c-x u equivalent).
4. A documented library interface (this is kinda #1 again)
I will eventually get around to making my own plugins to solve most of these. Its a matter of time vs tradeoff.
I think lem looks really promising, buuuut .., I like org and tramp and slime-connect and structural editing and all the other great emacs things. Maybe I’ll try it out in the next few months or so . . .