Would it be possible to generate personal API keys when you pay for a subscription? This way we can directly support authors using an existing system (well, once it's out of beta) while not being restricted to an app that we don't want to use.
The infrastructure is already there, just need to set up usage restrictions so it's hard to share. In the future it could even be made so that external parties can connect accounts to their CF account and use an API to fetch the key so you don't have to copy-paste.
Using the existing infrastructure for the API keys as created for 3rd party addon managers, this should be very little effort to set up. 3rd party providers could then provide a default non-monetized key which users could overwrite with their own. Additionally this would mean people could keep using their favorite addon manager despite being rejected for an API key for whatever arbitrary reason.
Sounds like a win/win for every party involved.