The repos are at close to 2000 packages now (you can easily search all that is available with the online package viewer, no need to install to check that), don't expect them to grow more then maybe to 2100.
If you are coming from Debian/Ubuntu/Mint were you had 60.000 packages available, you might want to rethink using a small distro like this......
Maintaining a few missing packages yourself makes sense, when that goes into the dozens (building the Gnome stack will be much more then that), it does not make sense to use KaOS.