I'm confused on the differences in repo priority between zypper (oS TW) and dnf (Fedora). Apparently dnf also allows setting repo priority, but I've never had to do it, and packages seem to come from expected repos without having to specify (stuff comes from RPM Fusion if I have those repos added). On TW I had to manually specify repo priority to something other than 99 and set a flag to allow vendor changes to have similar behavior; I like that kind of control but I didn't need to do it on Fedora.
OBS is nice in-concept but I don't like the idea of using it outside of openSUSE. I think Launchpad/PPAs for Ubuntu, Copr for Fedora, and AUR for Arch. I think OBS for openSUSE and don't like the idea of using OBS for other distros, even if that's one of the big benefits and point to OBS.