[kiryin]

First off, do yourself a favor and avoid snap like plague. It's vendor lock-in and horrible.

I use flatpak precisely as you describe. It's for graphical desktop applications, "apps", basically stuff like Firefox, Libreoffice etc. Sandboxing is cool but I mostly do this because the flatpaks are always up to date with respect to upstream, instead of locked into a particular version like in the system repos. I also recently ran into a situation where a particular application wasn't feasibly packageable by the distribution because of unorthodox dependecy choices (and their own, rather strict rules related to packaging), yet they made a flatpak available.

I also like the fact that the applications and their files are isolated in their respective directories, which makes purging unused stuff easy, as opposed to traditionally packaged software pooping all over my home directory.

Running stuff from the command line is a pain, thus why, at least in my use, it's limited to graphical desktop stuff that I'd anyway run by clicking on an icon.