I've considered it from time to time. The conclusion I keep drawing is that, if I were going to benefit from a selection-oriented editing paradigm, I would use Visual mode more than I do.

The multi-cursors, those I want. But I'm willing to wait for Neovim to get them.

That’s entirely reasonable; I switched in part because I was using visual mode so much. That being said, if you want a more vi-like experience in kakoune, you can always pipe your whole buffer through sed :)