The problem with that is that it lets your opponent know where your vehicles are going to land, which kind of defeats the purpose of deep striking. Unless you fake them out and arrive somewhere else entirely? Anyway, if they decide to aim lots of weapons at the landing pad, 4++ isn't going to help. It will soon be a platform covered with wrecks that you can't land on.
I don't think we're the army to hold a fort. Our biggest asset is our ability to be where our opponents don't expect us to be. Our weapons are surprise, speed, and cool dance outfits : )