I have created a couple of content types for H5P. Some have been released on the H5P Hub already, some are still waiting for review or release by the H5P core team. You can install the latter by simply uploading the demo contents that I have provided in the respective posts on this site to your H5P platform (if you have the necessary permissions to install H5P libraries).
For your convenience, I have created this list that will tell you where you can find the aforementioned posts with more details. If you install one of my content types that’s not yet listed on the H5P Hub, you should come back from time to time to check whether I have released an update. You can do that by comparing the version of the library that you have installed with the latest version that is listed down below.
P.S.: Yes, one could create an alternative H5P Hub server just like there are alternatives to the inbuilt app stores of your smart phone. That would, however, also mean to host that server and to create extra plugins for the different H5P host platforms to use it. Well, those could offer nice extras such as auto-updates, signatures for improved security, … But I am not planning to do that …