Ahoy, Kelly!
I remember being in your shoes two years ago when I was planning by family's adventures in Alaska. It can be overwhelming because many of them do offer similar experiences. I spent hours reading over Port Adventure descriptions and narrowing down my family's "must do" list before presenting my final selections to my crew. This is really the only way to figure out the differences prior to your cruise unless you wait to book at the
Port Adventures Desk on the ship. The risk you take with waiting is that your options may be more limited. When I was picking out my top 2-3 choices, I looked at the duration carefully because my crew does not like to be off the ship for the entire day and also took our budget into consideration. When we couldn't narrow down our choices, we booked more than one excursion in port if time allowed.
In each port of call we visited, the tour operators and tour guides were phenomenal, and they really made the experiences so memorable and fun! Each one was extremely knowledgeable that it was hard to pick a favorite out of the five we did, so I really don't think you'll be disappointed in whatever you choose to do! I do recommend looking at
Alaska's Whales and Glaciers Photo Safari in Juneau. This excursion visits the Mendenhall Glacier and offers an exploration of the glacier, the beautiful scenery and several mammals including whales, sea lions, porpoise and seals.
In the end, all the time I spent researching was well worth it! I also approached it with the attitude that we will visit again (wishful thinking!) so I didn't stress about what we were not able to do. It made it a lot easier to make our final decisions with this approach!
Good luck with your plans!
Nancy