An RV trip is just one way of seeing Alaska and what you see is south-central, central, and a few glimpses of the Panhandle at Hyder, Skagway, and Haines. Oh, and a very small piece of the North Slope via the Dalton "highway" (to use the term loosely). No one has ever driven to Juneau, Sitka, Nome, Dillingham, or Kodiak, but those are places worth visiting. So, multiple trips and multiple modes of transportation are needed to "see Alaska" and it cannot be done just from the deck of a luxury cruise ship, despite your friends having "seen Alaska" aboard the SS Volendam.
I calculated a while back that I have been to Alaska 17 times--mostly for work--since my first trip in 1972. And although I have stayed for months at a time and flown into places like Kotzebue, Unalakleet, Teller, Kobuk, Adak, and Shemya Island, I have not seen all of Alaska.
After your RV trip, you can take another by ferry, a third by small plane, another by kayak and small boat, and you will still not "see it all." So, don't worry about trying to see everything on one trip. Enjoy what you can see by road, then start making your list of all the places you want to go back to on your next trip!