Our new, not yet released Rust-based desktop environment for Pop!_OS and other Linux distros is filling out with some essential systems that cater the DE to both users and developers alike. Customization is one of our main focuses for COSMIC, and was a huge focus for us in August, too.
I can’t wait personally and will install it as soon as I can :) If it has some severe flaws, I just log out and log into Gnome or Plasma instead. It’s so simple.
Yes, it’s good enough to do many normal things with. And like you said, if you get stuck you can log out and into another DE. Logging out can be done from the top panel menu, the Launcher or using
loginctlfrom a TTY if necessary.