Many of our grandmas *did* feed commercial layer feed -- it's been around for longer than you might think. And the ones that didnt often lived on farms where the chickens scrounged grain dropped by other animals.
Also, our grandmas who didn't feed commercial layer feed did not necessarily have as good survival of their hens over the winter, or as many eggs.
There is a
big gray area between 'keeping chicken alive' and 'keeping chicken really healthy (which goes along with laying well)'.
In the best interests of the chickens, especially since you are new to them, it might be best to plan on feeding at least some reasonable amount of commercial feed, both summer and (certainly) winter. If they don't need it in the summer they prolly won't eat it but it will be there as a safety net, you know?
Otherwise you need to learn a WHOLE BIG LOT about poultry nutrition, real fast. "Just a simple recipe" is probably not going to cut it, especially since you're throwing in the variable of wanting to feed garden veggies as well. There is a LOT more to decent nutrition than it might seem. Whole books exist. For a reason
FWIW, I seriously doubt your chickens will *effectively* have 50 acres at their disposal. Most seem to stick relatively close to their coop. The ones that don't, you'll never find their eggs anyhow (and you may not find their remains after predators eat them, either) so if you had any like that they would not really be a functional part of your flock anyhow
Good luck,
Pat