LibreELEC provides an excellent platform for emulation gaming as there's no processes hogging the CPU. Also I apply -O2 compiler optimizations using gcc 7.1 and every emulator/core is built together with the OS. Combined with the latest Mesa version and 4.11 kernel it seems to work very well I had Arch working very well on my NUC previously though, but I rather like the simplistic nature of LE.
I don't know about attract mode, looks way to flashy for me. I can't see what it does better than either Emulationstation or RetroArch which is already included. Personally I think the best approach is ES with a list view and a nice theme. It doesn't really need any more development, it's already launching games which is what you need. RetroPie is working on adding features to it as well which I could pull in at some point.
Well escalade, I feel you about flashy frontends, I dont like either (coff coff hyperspin XD), but the reason is, and is a very personal reason, because of this
You know, flashyness depends entirerly of the theme you like to install, AM is very modular and dynamic, and more user-friendly to configurate than ES or HS or... I dont know
But, it is work and your decision man; but if you can help, or show the way to compile a personlized fork of your fork with all the patches you apply, would be awesome and super cool XD
Things I would like to include (or you could )
vanilla latest mame (retroarch mame still got some problems with a few games, and not, im not referring to a correct romset issue)
a virtual gamepad (like molten gamepad)
Keep the good work, you are a spot of light for our couch laziness