The first Alaska cruise we booked, I was convinced that it was going to be my ONLY Alaska cruise, as I don't do cold. I found that most Alaska cruisers say that Glacier Bay is a must (over Tracy Arm) if you have to make a choice. That being said, I was truly glad to find that Holland America had a cruise that included both Glacier Bay and Tracy Arm. The best of both worlds. I agree, if you're only going to do one Alaska cruise, Glacier Bay is much more dramatic than Tracy Arm. But, Tracy Arm is quite spectacular, also. Both definitely worth seeing.
We had longer port times (compared to
DCL) in the ports we visited, also. That gave us much more time to explore.
Of course, by the end of the cruise, I was smitten. We booked a cruise/tour for our next one. And we did the "big" one (as in 12 day land tour & 7 night Seward/Vancouver cruise), again with Holland America. It included the Yukon and many stops much further inland and north in Alaska than the cruise along the ocean can do. And, if visiting Denali, IMO, 3 nights there is important, as there's no guarantee you will actually even see Denali on any given day.
While we haven't been on Princess (yet), the Holland America ships are still in the style of "old-time" cruise ships. Although, they are a bit darker in their interior spaces compared to DCL. And there's only one MDR, although you can do assigned dining or can dine when you want. The buffet is a buffet for dinner, as well. There are 2 extra cost dining venues onboard - Pinnacle Grill and Canaletto. a couple of ships also have Tamarind restaurant.
We've found service for the most part was quite good, but can be somewhat impersonal on occasion. The "feel" of the onboard crew being "servants" more than "friends" is definitely there. But we were usually able to break through to our dining room servers on all our cruises with them and have fun.
Big plus, the pools are covered for the Alaska cruises (but covers can be opened on those days where the sun actually shines).