Bitcoin ad networks are really the only option for faucet / crypto sites due to the traffic quality.
Adsense started banning them last year even though they once allowed it... A-Ads, MellowAds + direct affiliate programs ease their way into making increased amounts.
I'd suggest inserting a mix of platforms so that more can be made with diversification.
Faucet owners can use many different low paying ads networks, but it's not enough to run a decent faucet. They must have creativity and programming knowledge to make a better faucet with some different features that make users enjoy their experience and make good returns.