I did actually give coc-nvim a try, and while it was effective for JS and Vue (the primary things I use VSCode for), I’m yet to find anything that can convince me to drop PhpStorm or Xcode for their respective specialties. So unfortunately it only solved about 1/3 of my problem.

I use coc-nvim and can attest that it is really good. I used to use YouCompleteMe, and while that plugin is really powerful it's also overly complicated and breaks a lot.