NAVIGATION AND TRAVEL
The problem: The map in Skyrim was impressive until you realised it was almost useless as a practical navigation tool. You couldn't zoom in far enough to actually see what was around you, and using the local map was far too complicated.
The solution: Keep the drawn out map from Skyrim but include granular details. Allow us to zoom all the way down to ground level and see what's around us, as if we were using Google maps to stalk our ex girlfriend. Which we've never done. Ever.
As for travelling around the landscape, horses were more trouble than they were worth. They ran off, attracted attention from the wrong kinds of people and ended up dying on a hillside. Red Dead Redemption it was not.
There always needs to be a happy medium between adventuring on foot and fast travelling; the latter is a bloody dull way to experience a Bethesda game, so there needs to be a way of getting around quicker that doesn't involve sitting through loading screens. Of course, horses might be out of the question in the Fallout universe, and we're not really keen on the idea of travelling the landscape on a clumsy Brahmin, which just leaves vehicles?
They definitely aren't going to up and leave you in the middle of the wasteland, and we've already seen the Enclave have the capability of using mechanised modes of hover transport, so hand us the keys to our own personalised, customisable wasteland ride.