Neovim feels indeed the proper future-proof evolution of a standard. Its still a bit cumbersome to setup (fonts, lots of plugins to configure, opinionated and overly decorated UI etc.). The acid test of maturity is the dry functionality you get out of the box in a fresh linux. It should be "just right", introducing the new thinking and functionality of neovim without getting in the way.
I actually like `nvim --clean`, which is just the basics. Early on in the Neovim project, a lot of heirloom defaults were changed to be more modern, resulting in a better (IMHO) out-of-the-box experience. I use `nvim --clean` as my man-page viewer:
MANPAGER=nvim --clean -c "colo sorbet" +Man!
Startup speed is blistering.
My current config is pretty stable, and not that large. But if it were causing issues, I'd seriously consider only doing LSP setup, which is not that onerous with the latest APIs (it was already fairly easy with `vim.lsp.start`, but `vim.lsp.config` and `vim.lsp.enable` make it easier still: https://neovim.io/doc/user/lsp.html).
