Reading this thread it came to my mind a simple idea: publish on the official store an app that simply showcases your apps then redirect to your site/store for downloading/installing/paying.
Fundamentally the app will be an advertisement, nothing more. For each app you show a description, some screenshots, a video, whatever.
This should comply with general terms for the official store, I guess.
It will be like a shop showing their weekly offer or catalog but needing you to go to the shop to buy items.