There’s mythtv, but it’s significantly more complicated than kodi and doesn’t have the streaming plugins. IME, mythtv makes a nice backend for Kodi, especially if you want to capture live TV OTA/cable. For just watching stuff, Kodi is great. It doesn’t really honor any file hierarchy you might set up under its “Movies” or “Music” tabs, but you’ll find that structure preserved in “Browser.”
I’ve found OSMC, which is just a dedicated OS wrapper around Kodi, a little wonky, but that could be just me. I’m used to ssh-ing in to systems to maintain them, and it took me a long time to understand OSMC’s connman network manager. I think it’s probably fine if you intend to interact only though Kodi’s on-screen controls, but osmc feels like a ‘weird’ linux. Doesn’t even log to /var/log/syslog
If it’s the control you find clunky, Kodi does support LIRC, and USB infrared receivers are like $20. You should be able to convince it to listen to your TV or universal remote for menu navigation, volume, etc, which will make it feel a lot like a normal/smart TV. I use the Kore app on my phone.
But UI is the Achilles heel of most open source software.