I've never personally used a GUI package manager. I just install an aur helper like yay and use the terminal, using the Arch repo websites to help look for packages when I need to.
I'm not sure why it might be bad to use discover. It's in the extra repo, not even from the aur. I would say you should backup, timeshift, and try it. You can always do a reinstall if you break something.
I did find this article which is not too old. https://www.debugpoint.com/arch-linux-gui-package-managers/
Out of this above list, I would try Bauh.