Not sure why people here are all arguing about why you would want to use discs, rather than the fact that the Steam Deck is a PC, of course you can absolutely used discs. All you need to do is plug in a USB disc drive, and it’s ready to go. I’ve installed a bunch of my older PC games from CD/DVD that way, and it works great. Even under Linux, applications like Lutris make installing Windows game discs pretty easy, and once they’re installed, you’re ready to go.

Yes, CUPS is what I’m talking about there being no good way of setting it up. (Obviously can’t be a flatpak, and no dice installing it with distrobox – trivially, at least – too tied to the system, I think)

I use it as my only personal (i.e. not work or shared) machine, and it is absolutely great. I expected to be installing a ‘proper’ linux distro on an external drive for the docked use-case, and it has turned out to be completely unnecessary. For those things not available as flatpak, distrobox/podman has been great. (The only thing that slightly irks me that is missing is support for a printing service, but I haven’t tried that hard to fiddle with that, since I can do it from my phone on those rare occasions I need to.)

Onlyoffice does now have an ARM version, I run it on a raspberry pi 4 (integrated with seafile), and it works fairly well. Can’t vouch for how much power it needs, to say if a pi 3b+ will be enough, though. Pretty sure it’s lighter than collabora, since more is done on the client side.

I agree with the other commenter that suggested cryptpad, though. If all you’re after is a Google docs like collaborative experience, cryptpad is brilliant, and much more resource friendly. (The office editor it uses is also a slightly modified Onlyoffice, so almost exactly the same feature set)

Most things, if not available as flatpak, can be installed inside another distro on distrobox. It runs in containers, so things can access a root filesystem (Just not the main SteamOS one), and is a pretty seamless experience, once installed. I have a bunch of non-flatpak software running that way, and it works great.

See https://www.gamingonlinux.com/2022/09/distrobox-can-open-up-the-steam-deck-to-a-whole-new-world/