My hubby and I (in our 30's) decided to book an Alaskan cruise a few months ago. After talking to a few folks that have been on this type of cruise, we were able to decide on our travel plans (including doing a one-way vs roundtrip cruise), cruise line, and the excursions we wanted to do. We live in Orlando and decided to fly into Seattle to explore, prior to going to Vancouver. A friend had recommended we go to Seattle the day before our cruise to see the Space Needle, the 1st Starbucks, Pike's Market and then take the Amtrak train from Seattle to Vancouver - it was the best thing we could have done and it worked out perfectly - I highly recommend this for anyone leaving out of Vancouver on a cruise! We took the 4 hr (very scenic) Amtrak train from Seattle to Vancouver (it goes along the coast) and that same day (in the afternoon), we left on our cruise.
Regarding Amtrak - we booked business class seats, but ended up spending the entire time in the dining car (tables/benches, electrical outlets to charge your phones/cameras, etc...). We were surprised how empty the dining car was the entire time because it seemed to be the perfect place to see the scenery, larger windows for viewing and picture taking. It was also super roomy!
Once we got to the Amtrak station in Vancouver, we took a taxi (no Uber in Vancouver) to the cruise port where we checked in, went through security, and boarded. If you go the Amtrak route, you won't have time to explore Vancouver, you go right from the Amtrak station to the cruise port (depending on when your cruise leaves, of course).
Our cabin was wonderful and it was all due to having a balcony. If we had an inside cabin or oceanview, our entire experience would have been completely different. You can sit outside on the balcony with a blanket (provided by the cruise in the pool area) and coffee and just take in the scenery. My hubby and I would spend hours on the balcony with our binoculars (highly recommend buying a nice pair of binoculars!). The binoculars allow you to confirm what you are seeing in the trees and water. We were in Concierge Class so we had fancy snacks delivered to our room each afternoon (they are just okay) and had turndown service. Our room attendant was a little on the creepy side, but that can happen anywhere. The bed was firm but comfortable - the tv is not the greatest but rarely do you watch it, you want to look outside any chance you get.
Very pretty port!
The most beautiful port!