I doubt we will see anything like Jamf App Catalog in Jamf School. If you compare the price per Mac device between Jamf Pro and Jamf School, you can see they know how valuable those extra tools are. Should something like that be added, the price per Mac device will most likely go up and hurt the selling point of Jamf School being a cost savings.
We have been making do with what we have available, and it has not been terrible so far. The ability to replace a package for an app in the details page makes it very usable for doing updates, as devices begin updating apps as soon as it sees a newer version. Adobe CC has been the only major piece of ****, but that's on Adobe, not Jamf.