By all means steal ideas from this; I probably stole them myself in the first place.
But keep in mind that this is the config of a non-programmer; I've just in the last week or two converted it over to Lua from VimScript; and I still only half-understand the whole thing.
Today I moved my whole configuration and vast array of plugins to mini.nvim and am blown away by its functionality and how quickly I was able to replicate -- error-free! -- just about everything I need in Neovim. (And also by how little I was actually using all the plugins I had!)
In other words, feel free to use this, but understand that, even though it's a lot sleeker and works better than it did before, it's no kind of model for a correct (or even fully working) configuration. Caveat Vim(tu)tor!