Completely blanked on early access pricing, so yes, if you bought it before release then it was likely cheaper still.

That is true, I didn’t even think of early access.

It’s reasonably easy to guess exactly what you paid for the game, since the only change in price since launch was a $5 bump in January last year. It’s never been on sale.

It releases while I’m on the way back home from a trip to Manchester, might have to bring my Deck so I can play on the flight/train.

Well, Flatpak always builds the aliases, so as long as the <installation>/exports/bin folder is in $PATH there’s no need to symlink.

If you’re talking specifically about having symlinks with some arbitrary name that you prefer, then that’s something you’ll have to do yourself, the Flatpak applications only provide their canonical name after all.
You could probably do something like that with inotify and a simple script though, just point it at the exports/bin folders for the installations that you care about, and set up your own mapping between canonical names and whatever names you prefer.

In regards to sandboxing, it only gets as far in the way as you ask it to. For applications that you’re not planning on putting on FlatHub anyway you can be just as open as you want to be, i.e. just adding / - or host as it’s called - as read-write to the app. (OpenMW still does that as we had some issues with the data extraction for original Morrowind install media)

If you do want to sandbox though, users are able to poke just as many holes as they want - or add their own restrictions atop whatever sandboxing you set up for the application. Flatpak itself has the flatpak override tool for this, or there’s graphical UIs like flatseal and the KDE control center module…

Well, if you have any form of build script, makefile, or CI, then you can easily shove that into a flatpak-builder manifest and push the build repo anywhere you want. The default OSTree repository format can be served from any old webserver or S3 bucket after all.

I’ve done this for personal projects many times, since it’s a ridiculously easy way to get scalable distribution and automatic updates in place.

The majority of AppImages I’ve seen have been dynamically linked, yes. But it’s also used for packaging assets.

As long as your application is statically linked, I don’t see any issue with that.

Well, Flatpak installs aliases, so as long as your distribution - or yourself - add the <installation>/exports/bin path to $PATH, then you’ll be able to use the application IDs to launch them.

And if you want to have the Flatpak available under a different name than its ID, you can always symlink the exported bin to whatever name you’d personally prefer.
I’ve got Blender set up that way myself, with the org.blender.Blender bin symlinked to /usr/local/bin/blender, so that some older applications that expect to be able to simply interop with it are able to.