hbrady, you mention that you have not done much towing -- in my opinion, after a lot of towing, I have discovered that there are many times when you want as much rear visibility as you can get. When I am towing, I try to maintain a good mental picture of a big oval around me and my trailer -- front, sides, rear -- at all times. That way, if I have to make a sudden move to avoid a hazard (a box falls off a truck -- a clown is texting and drifting over --etc.) -- I can do so more quickly.
Only the paranoid survive. Sad but kind of true.