It’s interesting but I’ve not had any performance issues running Kodi on anything from a fire tv to a Chromecast to windows to Linux (Ubuntu). I don’t run a ton of plugins but the ones I do work almost flawlessly most of the time.

I will say that a couple of years ago I moved to using the jf server connected to Kodi and that seems to be the best of every world. I get the Kodi interface (jf didn’t have themes and it is still really unintuitive to me) and I get a single repository for my multiple clients.

All of this is to say that perhaps Kodi isn’t as bad as you think it is just because you had some issues with your install.