It doesn’t make a big difference so if you install one of Flatpak oder Snap anyways for something else, stay with it. Otherwise I’d recommend Flatpak since it is somewhat native to Arch and there are many guides on how to configure it. Like @julianh@lemm.ee said, your privileges issue can be resolved. You don’t need a GUI for that, just follow the documentation, it’s pretty easy.
It doesn’t make a big difference so if you install one of Flatpak oder Snap anyways for something else, stay with it. Otherwise I’d recommend Flatpak since it is somewhat native to Arch and there are many guides on how to configure it. Like @julianh@lemm.ee said, your privileges issue can be resolved. You don’t need a GUI for that, just follow the documentation, it’s pretty easy.