It would be interesting to add a context menu, where it would be possible to select which version of the application or game the user intends to install (beta or stable version). This feature would be very interesting in gnome software too.
This is realy important for sofware with not only development, but testing, stable and long term support. This is specially true for LibreOffice. The user will be forced to use the latest version in FlatHub, but it can’t choose to use the long term support version, so the user will test the application, while may can just use the more tested version for its work.
This is already in place in gnome software, if you have the beta repo installed How to use flathub-beta