Fair, ads should be viable, but OP really didn't try very hard on that front. There are plenty of ad networks that could be a substitute, but I understand that they're not as good as Google ads, and OP is lazy.

Buy Me a Coffee is not literal, it's a service to collect contributions.

I like the idea of microdonations, and I think it would be healthy for the ecosystem if sites could implement one-click 50 cent paywalls, but that's pretty far off.