One of our more popular publications for downloading is the chicken tractor plans. I always field questions about the plans every year. Some ask how many chickens will it hold; others ask about the construction, or to clarify something in the plans.
One recommendation or change I always make is to increase the height of the front cage area. The current plans make it so short that you need to stoop over to get inside. Why not make it high enough to walk in upright? The material cost will not increase that much, and its much easier on your back if you need to work inside the coop area.
We have not made this change to our chicken tractor, or to the plans, but it simply requires four taller posts, longer boards for the door, and some additional chicken wire. So far no one has called me back to say it did not work.
Feel free to experiment with the design. I have noticed numerous versions of the chicken tractor online. Everyone has some new ideas on how to build a chicken tractor, usually customizing it for their operation.