Free ranging a lot can cut down on your feed bill. Organic feed certainly costs more, but organic eggs can command a higher price. I feed mine organic, and can get $5/doz. I have a waiting list for my eggs. Of course the market dictates this a bit.
There is a fair foods market in town that charges $5 for brown and white eggs, and $6.50 for blue/green eggs. All pastured and organic of course.
You may be able to find a niche market by feeding a soy-free and corn-free diet. People with severe allergies to these foods can't eat "normal" eggs because some of the allergens are transferred to the egg. I know someone who gets $7/doz. for these.
But I agree, if you're going to do it on volume, you need sexlinks, or leghorns, or one of the prolific laying breeds. I try to put a blue and a chocolate egg in each dozen, but they lay half as often as the production hybrids.