We did a 2 week trip to Glacier back in 2004. Had a good time, but I prefer Yellowstone.
Anyway, when we were there, the West side of the park was better (less wind). We drove up to Waterton Peace Park (actually towed my boat up there). Very nice, but too much wind to use the boat. Actually it was so windy that I didn't launch the boat our entire trip to Glacier.
On the way home, we spent the better part of a week at Flathead Reservoir, between Misoula and Kalispel. I liked that part of the trip better personally.