Since you are there before the beginning of the tour buses in Denali, I would explore the Kenai Peninsula. Take the Kenai Fjords tour out of Seward one day. Go Kayaking on Resurrection Bay there in Seward. Take the Glacier tour out of Whittier another. Spend a day or two in Homer. Plenty to do in that part of Alaska (assuming that the weather cooperates). If you like to fish, go Halibut fishing out of Homer, or Salmon fishing in Kenai or Soldotna.

Lots to do. Enjoy.