My neovim configuration uses NVF. NVF is a framework for running neovim on nix. It gives you the best of both worlds; the granular control of Lua, and the simplicity of nix, along with the ability to manage all deployment through nix. Been using a while now - delighted. Below is a recent Vimjoyer video for those who are curious.
https://www.youtube.com/watch?v=uP9jDrRvAwM&t=4s
It took me quite a while putting this config together as there was nothing to crib from when I made it. Hopefully it may serve as a base template to someone, and if you have any cool improvements, feel free to let me know.
I personally prefer small modular files rather than lumping everything in a few files....
Any decent base16 themes always welcomed!