No, I mean an editor that allows you to build a complete vim with macros, for example. The source for vim wouldn't be in C and you could implement plugins like EasyMotion.
Only if you want all the stuff (including crap) that vim offers. If you're OK with the 50-100 core commands, then those emulations can be perfectly fine.
(Also some of us used vi too, and that didn't have all the stuff vim comes with either).
You mean like vim-mode is already existing in every editor worth to be called editor?