The most important and almost constant use of the LAN here is streaming video or music files to the Raspberry Pis that drive the TVs. Over the years I've gone through various hacks driving TVs direct from my computers to one of the early ASUS made digital video player things (GPL violations R us!); to a LibreELEC setup that worked for us.
In that time Esme got a TV too and we drove it variously with a couple of android tablets running VLC and then a clone of my RasPi/LibreELEC setup. She was so happy when we did that, and the microwave no longer eliminated her wifi signal. The choice between food and TV was often hard for her.
Now I've got my new office and that means yet another TV; which is the perfect opportunity as it happens. I've deployed a new updated version of LibreELEC (which i couldn't before as they'd no longer speak to Myra's SMB) to my new TV, set it up to use the new media library on snafu; and then clone it to the other TV Pis.
It took a solid 12hr for the media metadata to load, I'm not using any of the "Media Center" systems for that yet and the result isn't great, but works well enough for now. Once its all set up, put it on another RasPi, take an image with:
sudo dd bs=4M if=/dev/sdb | gzip -vc1 > raspi-card.img.gz
Put such an image back on a new, unmounted card:
gzip -dc raspi-card.img.gz | sudo dd bs=4M of=/dev/sdb
/dev/sdb with the location of the card you want to
read and write; this will cheerfully blow away a running system if you
mix that up.
I use a disposable RasPi image for a utility desk machine that does these tasks, and so that kind of error isn't a big deal here anymore... I learned the hard way a couple of times.
I've set our TV Pis up with these lovely Logitech keyboards, they're not something I'd want to type on all day but they're excellent for our purpose here.
These are viable enough input devices that I plan to have another tangle with compiling kodi and make a fancier "TV Client" system with web browser, selected games, etc. By the time I get around to that, the efforts of others may have provided everything I need... If indeed that's not already the case.
This worked smoothly and my users noticed the look and feel upgrades to Kodi but otherwise their user experience is almost unchanged. Improved in fact, because of the real and substantive improvements that the Kodi and LibreELEC teams have been putting in.
This whole thing has been one of the most satisfyingly justifiable sysdamin type projects I've ever undertaken; little girl watches her cartoons whenever she likes, she did before, she does now, and she didn't really notice a change.