i visit the tetons and glacier a few weeks every year for vacation in september & october. sometimes i'm lucky to hit it when the leaves are changing color, sometimes not. landscapes are pretty standard stuff. but a 100-400mm lens is a must if you want to capture any wildlife in wyoming. the bears are closely monitored in the tetons and their schedules are known by the park rangers. the rangers are usually on scene before the bears cross the roads and keep the crowds pretty far back. i've had better luck finding wildlife on the east side of the park than on the west side. check with the lodges, they're usually a good source of rumors on what animals have been spotted where. the best time of day for moose is dusk and very cloudy mornings, bears seem to be late afternoon, though we almost hit one that ran out in front of our car last year.
this was with the fuji x-t2 & 100-400mm @ 400mm. i'm seriously considering coupling my 70-200mm with a 2x teleconverter on my 6d this year.