Hey
ramz8453
I agree with
fischnchix the bigger the run the better, depending on your climate you may find your chickens spend the majority of their time in the run and only go into the coop to lay and roost; that is definitely the case with mine.
I mainly wanted to reply with regards the free range.
Granted, I only have bantams, but I have very low fences around my property and in the two and half years I have had chickens, they have never tried to jump the fence. They very rarely wander out of sight of the coop/run.
However, because of neighbourhood dogs and cats, free range is always supervised and for a couple of hours each weekday afternoon and the majority of the day on weekends.
I totally understand your concerns about the highway and that is similar to my concerns about the neighbourhood pets, but, if you wanted to, you could try letting them have a supervised wander and if you do this over a period of time they may be like mine and learn not to stray too far.
When I used to catch the bus to work every day, there was a house across the road from the bus stop who had a couple of Turkeys and heaps of chickens wandering around in the front garden with a very low fence; I used to sit there every morning watching them all peck around, totally unconcerned by the number of cars, buses etc speeding past.
That was not intended as a criticism of your decision to not free range them, just a suggestion if you did want to let them out for a wander.
Spending a Saturday or Sunday in the garden with little chicken helpers is very enjoyable