Additional question: wouldn’t it be cool to have a place where you can only get open source stuff? Obviously there needs to be more to it than this fact i presume but its a start.
F-Droid isn't the only one: I also like Neo Store, which has more than just the F-Droid repository and I think has a better interface. However, I think not all repo are 100% safe because F-Droid verify all the apps they have while Neo-Store doesn't because it simply list known repos, which you can activate however you like in the settings.