The front doors became more popular on a Diesel pusher because of the slide-outs. The mid door cuts down on slides on the passenger side.
We have our door in the front and the passenger seat sits a little higher and slightly back. I don't see a problem with this as I'm concentrating on the road. We have no problem with conversation back and forth. Our driver/passenger area is a couple of steps lower than the living room. This allows for a full view out the front window while sitting in the 'salon'.
Newell makes a mid door four slide coach. The mid door takes up bay space that is not added to the front. But, I'm sure that's OK with someone who wants a mid door.
Buy and drive what YOU like, you are the one who needs to be satisfied.
MM.