I think about writing the config in fennel all the time, but I’m not a big config tinkerer and already worry about struggling with Lua when I have an upgrade gone awry.
I’ve found the neovim ecosystem to churn way more in recent years than it did when I initially started using it 8 years ago. It really reminds me of the JS ecosystem of the past decade: full featured plugin that works great decides to strip things back so that it’s functionality is all plugable and you suddenly have to wade through 2 major release’s migration docs to get things kind of working like they were before. I digress to point out why it might be hard to have yet another layer to translate through. Though if you don’t have kids, I’d say “go for it!”