If United get their targets, then adding Hummels, Shaw, Strootman and Reus to their team will definitely improve them. Gaining an understanding is the problem, but they could just gel.
Van Gaal has a big job ahead in rebuilding a team left in a perilous position by Fergie. Moyes didn't have the right talents to rebuild and play successful football at the same time. Jose does, which is why we hung around the top end of 2 big comps with a team without strikers and a badly matched and misfiring midfield. Van Gaal does seem to have the experience needed to build a long term team and up the standard of play. He may not be the best strategic manager going around, but Utd are at least a whole season away from being able to concentrate on tactics and not on rebuilding. My tip is he will do OK.