Just returned from Alaska, we did tour 5B, which is 5 nights prior to 7 night cruise. This takes you to Talkeetna, Denali ( yes we saw Denali ) and then to Alyeska Ski Resort. This tour does include RCCL's train ride for 1/2 day where you will see tons of wildlife ! The weather was perfect, in fact a bit too warm, but no rain at all.
We flew into Seatle, stayed 2 nights, then flew to Anchorage which is where the land portion begins, and cruised on Radiance, which is showing her age. Now that Ovation is there I would look into that instead.
We saw tons of wildlife, grizzly bears, black bears, eagles, moose, caribou, sheep, goats, whales, sea otters, sea lions etc, I highly recommend this cruise and/or land portion !!