I like that solution. Indie’s buy once while Enterprises are limited to use our products through license subscriptions.
FAB/Epic would need to enforce it. Just like Autodesk or Apple, when you register as a Company (BIN #, etc)… they’ll have benefits and different obligations than Indies. For example: Big discounts for Enterprises after purchasing a number of licenses (Autodesk) or having your company name next to your Apps in the App Store (Apple).
Epic can similarly offer Enterprises benefits while using FAB. If they do it well, it can Boom just like the App Store and become Epic’s #1 source of income. In addition, they will have a steady income like Autodesk/Apple and stop relying on indie Game sales. It’s a win / win for them, Devs and Artists.