I can be picky about my advertisers. But until recently I didn't realize I could automatically approve anyone that I've allowed to advertise before. Just go to advert settings in your dashboard:
Now, click both of the options, including Accept ads automatically if they have been approved previously.
I wasn't aware of this when I first started using EC, so I was having to go back and re-approve blogs that wanted to advertise a second time. This setting keeps me from having to manually approve trusted advertisers.