I would have thought that creating/adapting a colour scheme is a onetime activity when you start using the editor for your language. Do you update the colour scheme regularly?
As others have said, the appeal of Kak is orthogonality and accessibility. The keybindings are sensibly organized, there is exhaustive autocomplete and on screen documentation, and the configuration language is simple. It is ridiculously easy to write plugins for, because you can use shell scripting, or create a program in any language you want and invoke it from a shell block. Kakoune's LSP plugin is written in Rust and communicates with Kak via the shell.
https://github.com/raiguard/one.kak/blob/main/colors/one-dar...