KDE Plasma may be a lot more customizable than Gnome, so you might be able to find something more like what you are looking for there. I would do a web search for varied examples if I were you.

You could search for more Gnome examples too. I believe Gnome requires more in the way of plugins for customization, so you might have to seek out examples of gnome plugins that customize look and feel or window styling. I’m just speculating here, I don’t really know Gnome very well.

The readme doesnt ever explain what a smart playlist is. Is this a term that most people know that i’m just out of loop on?

Seeing them phrase it in bullshit business-speak really increases my confidence.

You might also consider openSUSE for btrfs snapshot rollbacks in case something breaks (though tumbleweed is quite stable anyway). They also have community packages.

Were you able to reduce the latency to acceptable levels?

People keep talking about needing to “organize your library” but what do you mean by that? Is metadata tagging sufficient? Or does Kodi care about filenames and directory structure?