For me CPX works quiet good. From the statistic I see, its not about Cost per Click. It pays on Cost Per Impression which is like very less. But they pay more by Cost Per Conversion. I tell you, you might think it will be hard for getting some conversions but its not true. I get lots of conversions daily. You can try them. But for getting CPX you need to have a site with really high traffic. Apply to them. I applied 4 times in last 2 years. Only two months Ago i got my Approval. You can set the minimum payout. But its 20$ I guess. I never got a chance to see the minimum payout becuz within couple of days My total was more then 20. I suually keep it on 100.
Have you tryed removing or declining ads? You can approve only just ads targeted to you niche. and decline all the other ads.
I will try now. I dunno much about whats my niche though as Mine is a general forum discussing everything from start to end Let me give it a try though