My family and I are debating on which trip to take. We have a 12 year old and 9 year old. We want to see Yellowstone, Grand Tetons, RMNP, spend some time at a ski resort during the summer, and possibly a day in Denver. I have been advised to divide these into 2 separate trips, which I appreciate, by flying into SLC and doing Yellowstone/Tetons or flying to Denver for possible Vail or Breck and combining with RMNP. Which would be a better trip with 8 days? We love sightseeing, all outdoor activities, but also enjoy resort time/relaxation. Suggestions welcome. Thanks in advance!