Unfortunately Alaska is not a place where you can "base" yourself in say Anchorage or Fairbanks and take many day trips. The distances are just too far. Therefore, using points for hotels to stay in Fairbanks or Anchorage might save you money, but it is a very poor use of time if your goal is to see Alaska. And this is even moreso the case if you are interested in seeing nature, wildlife, etc. You won't see that parking yourself in a hotel in Anchorage or Fairbanks (at least the chances are greatly reduced - there are occasional moose in Anchorage for example).
July 4th is incredibly busy in Seward, so unless you go earlier or later, forget that. You really need to think about staying in places like Healy or Carlo Creek for Denali.
How many nights are you planning on staying at Denali? You mentioned Kantishna and Wonder Lake bus tours. Do NOT take a bus "tour" but take the shuttle bus. Same road, same wildlife, and 1/3 of the cost, not to mention that you can get off the shuttle buses to hike and hop back on another one, something you really can't do with the tour buses. Also, Kantishna is really not that interesting - mostly private land. I would book a shuttle to Wonder Lake. If Mt. McKinley is visible, stay on the same bus to Wonder Lake. If the Mountain is not visible, get off at Eielson and catch an earlier bus back to the entrance.
For Seward, I would suggest staying in Girdwood for two nights. You could stay in Anchorage, but you add an extra 2 hours round trip of driving to the trip. Something like this:
1 day drive to Whittier, take a glacier tour in Prince William Sound, overnight in Girdwood.
2nd day drive to Seward (allow 3 hours with stops), take 11.30am Kenai Fjords tour, drive back to Girdwood
3rd day drive to Denali
Note that you might see whales on the Kenai Fjords tour but it is definitely not a whale watching tour and people usually only see whales on those tours about 50% of the time.