Hi Rusty,
With my low hiking shoes I can get the pants on or off with the snaps closed if I take my time. You should make the legs just a bit wider if you don't want snaps or zippers
The snaps are for more then one reason. I can unsnap a few of them to vent my lower legs as well as pull them up and sort of turn them into a pair of long shorts.
If you recall from the "Pants" thread, Jhaura, offered to put snaps on something for me. Then within the last year he offered his snap machine for sale and I bought it. The next time I come across my Pants pattern I am going to make another pair and use those type of snaps. I will make the Pants so I can roll them up above the knee and use them as a pair of shorts.