If you don't want to cull any birds, some thing to maybe try. Does where they free range have food available for them to find? If so, Can you free range them all day? The more they find their own food the less you have to feed... hens will usually come back to the coop to lay if they are used to it. I would also feed them in the evening so they spend all day looking for food instead of eating what is easily available. Also soaking/sprouting grains or using a fodder system is something to think about.
Ya, cut by adding something cheaper or a lower protein percentage. Most Layer is 16%, if you buy 20% you may be able to wind up with a total that is cheaper if you cut the 20% with corn/oats/wheat etc down to 15 0r 16%. Local mills may also have something like Distillers grains or Corn distillers, it is usually fairly cheap and you can add it as a protein supplement. Protein=money, The commercial Layer foods are all around 16% since that is apparently where the cost/benefit ratio of protein to egg production is best for the commercial flocks. Note that some of this (lowering protein, feeding less etc) may cut your egg production to some extent. Also, mash is usually cheaper than crumbles or pellets, there maybe more waste with mash, but if you are willing to feed it wet, (more labor intensive) it may come out cheaper in the long run (here the mash is more than $2 cheaper than the pellets).