I was thinking about some kind of door that would have a full shell that would seal around the door frame, just like stock, used the factory lock and handle /push bottun mechanism (only with the handle part cut off) but had a removable canvas/waterproof fabric with a sewn in window. I was thinking you could wrap the material around the entire door and then have snaps on the inside edge of the door all the way around to snap it to. This way when it rains (you never know when in Oklahoma) you could have a waterproof door and then for the calm after the storm you could pull the fabric off and viola! you're practially doorless. Plus all the added features of a way to lock it.
Something like this only with the push button and lock
Something like this only with the push button and lock