All are good choices. Each has strengths and weaknesses.
7mm less recoil for great and adequate performance for your needs. Less barrel life, less efficient.
300 WSM, WM more recoil but more downrange energy potential. Better barrel life, more efficient.
Pick your poison. They're all good for what you're trying to do. If you ever decide to add another couple hundred yards to the elk equation, you might think about the larger of the three.