IMHO, there is not real decent alternative. All of them are bleak and static. It's just sad. =(

HAL Launcher. You can customize it and change the background colours to not make it look so bad

Not a launcher exactly, but Kodi can launch apps from inside it's own menu. So if you can get it to start on boot up, you could customise it how you want it to look.

ATV Launcher Pro

Atv pro or wolf launcher decent enough if you don't like suggestions on a default gtv launcher and plan to sideload apps

I just use the original launcher in the mi box.

Disable auto updates on google play store (user icon -> settings -> auto update) Go to settings -> apps and uninstall "Android TV Home"