Is a challenge then perhaps subscription payments? Would you consider other models like freemium/premium, etc?

I don’t know of many fully donation or any value for value business cases that have been sustainable for tech products. Extra revenue maybe, but never primary.

I think payments will start to get larger using Nostr. As people feel more comfortable with wallets and payments are not scams, the transaction amounts will rise (even if just targeted ones and the median/average) remains micro.