I've heard plenty of good things about Steam Deck. If I wasn't on a college budget, I'd definitely be picking up one (most likely second hand to save money).
I was incredibly stupid and did buy it as a laptop replacement. The thing does what it was sold to do extremely well, but I have little Linux experience, and trying to learn Arch on SteamOS has been hell.
You shouldn't need to use any of the Arch stuff on Steam OS. It had a read-only root, so you'd need to disable that to use any pacman commands anyway.
You should be able to get everything you need through the Discover store, since most applications are available through flatpak. That should be a similar experience as any other app store, provided you know what you're looking for.
The main issues imo have nothing to do with Linux, but the form factor:
screen to small to use for reading text
no keyboard, so that needs to be brought separately
doesn't stand up on its own, so you'd need a stand
awkward shape for fitting into a bag with other stuff
If you're always plugging it into the dock, I'm not sure why you wouldn't just get a desktop or something and keep your data on a USB drive or in the cloud. If you use it even occasionally as a mobile computing device on battery, just get a laptop, that's what they're designed for.
You are absolutely right. My problem was trying to install a hex map-making tool for D&D, which only came as a .deb file. So I needed a tool to install that, and the tools I found needed pacman to install them.
In regards to the decision to purchase a steam deck as opposed to a desktop or laptop, I most likely just wanted an excuse to buy a new toy, justified as a way to replace my aging laptop. I'd love to say it was a younger me making that mistake. No, it was me one year ago. I'm not really a different person now, and would likely do the same thing given the chance.
Where can I get a steam controller dirt cheap? I’ve wanted one since I got my SD but any of them in decent used shape seem to go for $50-60 and often are missing the dongle.