I've been to Alaska twice, by plane to Anchorage, and by car to Skagway. In both cases we drove when inland, and made use of the Alaska Marine Ferry to move between some of the coastal towns. I didn't have the gear I have now. First time was film cameras and a compact digital. Second time was DLSR with the two basic kit lenses plus some compact digitals. I could get by with my EM5, 14-42 and 40-150 if I went again, but of course I gotta have my 9-18, and the fast primes. Add the fisheye too.
Weather and luck will probably be a greater factor in your photography than your gear. On the coast. it seemed like it rained every morning, but often turned sunny in the afternoon. When you are subject to the schedule of cruise boat excursions, you might catch a good day or a overcast one. We took the White Pass train ride out of Skagway and it rained and turned partly cloudy, However, we already had seen a lot of that country driving south from the Yukon, and we stopped as needed to look and shoot.. It was overcast every day in Juneau so we never saw the Mendenhall glacier in the sun.
We didn't go looking for wildlife much. I spent a morning looking for eagles at a bird refuge near Haines (which is so dead that the cruise ships no longer stop). Nada, unless you count birds high in the sky. Then we stopped at a McDonalds near Sitka for burgers, and the waterfront was full of them, close enough to use the 40-150. A passerby told me they called them dumpster chickens.
Denali is a different. Our bus had bears circling it..
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