I personally find people are more willing to buy a chicken if it costs $20 or under. So, I would raise them a bit smaller. Chicken will forever be viewed as 'cheap' food, suitable to feed 2 people for 1 meal. It's very hard to get people to realize you can have leftovers from a large bird, or...
Someone is doing organic near me and he's at $4.85 per lb.
I'm at $3.75 per lb conventional; although I feed them a certified vegetarian feed which is a little pricier than the cheapest broiler ration I can get.