FWIW, I consider the Paxson-Cantwell drive one of the most scenic and enjoyable in Alaska. Yes, it is on a gravel road; yes, it is rougher than a typical gravel road in the L48; yes, your rig will get dusty and dirty.
If any of those are barriers, then don't take this trip.....but if you want some scenery and a good chance to do something more akin to "camping" than "RV'ng", then the Denali is a good place to go. I'd suggest taking at least 3 days / 2 nights to make this trip, if not longer. Scenery, opportunity for campfires, interesting spots to walk around/hike, etc. make this a good place to see a bit of the country other than the typical "tourist trap" spots.
And afterward, there are lots of places in Wasilla/Los Anchorage/Squarebanks to wash the rig, rent a room, get a full-hookup rental spot afterwards to cleanup and wind down.