[viksit]

Agree with your high level point. Mine isn't that because it's written in e-lisp, emacs supports every other lisp. The fact that it's written in e-lisp makes it very extensible, and some standard things like C-x C-e to evaluate forms et al, which were originally developed for and are the standard for e-lisp, have been adopted for all other lisp modes as well. The very fact that the editor is written in a lisp makes it expose useful functionality this is useful in other lisp contexts.