Classy way to hide unused low voltage cut outs or should I just drywall over and paint?
If there are live connected wires in any of those junction boxes then you cannot just drywall over them. They have to be accessible, so stick with the cover plates. The low voltage ones could be patched over and the walls painted. Just take some good measurements for the future. In 5 or 10 years everything will probably be wireless and we won't need any wire for anything...