Can anyone recommend a good advertising service? Google Adsense doesn't count

In January we moved to a third party ad system instead of selling own own text ads, but we're not happy at all with the company we signed up for - The Rubicon Project. They are like a middle man and serve ads from various other advertising companies like Google, Yahoo, Active Response Group, CPX Interactive, etc, and theoretically optimize them over time based on each network's performance to earn us the most money. That optimization is a fairy tale unfortunately, and doesn't so jack diddly. Plus we've had two major problems with the service, including them not paying us for our first month even though we had earned WAY above the minimum threshold, and both times their customer service sucked big time. And the ads are extremely irritating anyways, and that's not at all what we want.

This company has a raised $18 million in funding which is just unbelievable. There's no way they're using any more bandwidth or resources than Clicky is (they're still in private beta), and we started on essentially zero dollars from our own pockets and have taken zero funding and have zero debt.

So we're looking for a new service. We don't want Google Adsense because it doesn't work well at all with our type of site, since there isn't any good content for them to spider. We have Adsense activated with Rubicon right now and all it does is advertise other analytics products, in particular Google Analytics. Gee, thanks :P

Between getclicky.com and our Freewebs partnership site, we have close to 20,000 visitors and 150,000 page views per day, so I think that makes us eligible for pretty much anything. We'd prefer to do text ads, and have them CPM based rather than CPC/CPA. We'd be ok with graphic banners too as long as they aren't super annoying, but we definitely like text better. It would be really sweet to be able to pick our own keywords for the ads to be based on, or very specific categories (not "Technology" which is the only thing even remotely close to us with Rubicon). We have a VERY targeted user base (people who run web sites, mainly blogs or business-related) so I know there's something out there waiting for us that will surely bring in billions, it's just a matter of finding it. Any recommendations would be very appreciated.