You can choose ad network by countries, ad formats, stream, min payouts, frequency payments, payment systems, and CPMs with our free tool adspyglass.com/best-ad-networks
For example, for mainstream, popunder, USA, best ad networks with Bitcoin payments:
popcash min payout $10, frequency - on request, CPM $1.63
Adsterra min payout $5, frequency payments - bi-weekly, CPM $0.92
Adcash min payout $25, frequency payments - monthly, CPM $0.71
You can check all these data for your countries and choose the best ad networks for your traffic.
Also, note that a new ad format Interstitial has been launched for mainstream and adult sites. CPM is similar to popunder and Google doesn't block sites for this format.
For example, CPM rates interstitial vs popunder:
Russia: Interstitial - $0,45, popunder - $0,92
India: Interstitial - $0,28, popunder - $0,25
United States: Interstitial - $2,19, popunder - $1,07
Germany: Interstitial - $1,15, popunder - $0,72
France: Interstitial - $1,08, popunder - $0,68
United Kingdom: Interstitial - $2,27, popunder - $1,17
Brazil: Interstitial - $0,30, popunder - $0,36
Romania: Interstitial - $0,43, popunder - $0,46
Spain: Interstitial - $0,68, popunder - $0,58
Italy: Interstitial - $0,26, popunder - $0,62
Canada: Interstitial - $2,26, popunder - $0,92
China: Interstitial - $2,02, popunder - $0,83
Thailand: Interstitial - $0,88, popunder - $0,51