My opinion sailing round trip from Seattle you spend way to much time sailing through Canadian Inside Passage instead of Alaska Inside Passage.

To answer your question, Glacier Bay is magnificant and requires very difficult permits to visit,which is why not all the sailings include Glacier Bay. Sawyer Glacier and most any other glacier that the big ships visit is equally as spectacular. I do not think you will feel you missed something without Glacier Bay.

Since you mention you want to be outside, Do realize that you will be spending most of your time on a ship?

I've been to Alaska once(no cruise) and loved it. My parent did an 18 day cruise/land. They thought the cruise was nice for 8 days, but really enjoyed the land portion much more.

I personally wouldn't do the cruise unless you have several days to do land too. I haven't been to Glacier Bay, but it is high on my list. I will spend a few days just there when I do go.
Alaska truly is amazing, but it is big. That is one of the good things about seeing it from a ship. So, I do understand why thousands of people choose that mode.

Glacier Bay, YES! I feel strongly that to "get Alaska" you need to do a combination of land along with the cruise. Look at Princess and HAL cruisetours unless you decide to try your own land arrangements. Look at those that include Denali NP. PS, Seattle then may not be your flight destination maybe Anchorage, Fairbanks open jaw? Just my opinion.

Do visit Glacier Bay. Ships are charged a fee to enter and numbers of ships allowed is restricted which accounts for those itineraries skipping it. We cruised from Juneau to Sitka for a week with Lindblad, a wonderful small ship experience. We also spent ten days in the Kenai Peninsula, Anchorage and Talkeetna, renting a car and driving.

I think a small ship is an entire other ball game. I would love to do that.

Glacier Bay was one of the highlights of our HAL cruisetour. It's definitely worth seeing, and we didn't see anything like it during the rest of our trip.

It will be "important" IF the following things happen IMO

you are there when a bunch of ice cleaves off the glacier just like in the movies

you have a pair of BINOCULARS so you can see it up close just like in the movies

and those things happen in other places BTW

Holland America has RTs from Seattle that visit Glacier Bay, other than that there is Sawyer & Hubbard Glacier. Hubbard is so big, you can watch caving with the naked eye. I do 2nd Cranachins rec of HALs cruisetours. IMO- GB isnt a 'must' but if its not much trouble probably the best of the 3. If you want my 'must see' it would be a stop in Sitka

I'm not sure if any Seattle departures go to Hubbard Glacier, and only a couple of round-trip sailings from Vancouver do so (in particular Celebrity.) Hubbard/Yakutat Bay is considerably farther north than the rest of the Southeast Alaska ports of call the round-trip boats visit.

For the OP, this is an important point. Because of federal maritime law, one-way sailings between Seattle and Alaska can't be done, so you have to do a round trip only. Because of time and geography factors, the Seattle departures typically travel to the west of Vancouver Island, on open ocean, in at least one direction. This passage can be a little rough and it's definitely not scenic, especially when compared to the more scenic and calmer waters enjoyed by ships passing to the east of Vancouver Island. Departures from Vancouver BC do this, and because the same US law doesn't restrict sailings originating in Canadian ports, you have a choice of a round-trip or a one-way itinerary to Alaska - either Vancouver-Vancouver, or Vancouver-Seward/Whittier (or v.v.) Prices are comparable to Seattle departures, and, in my view, it's better value.

If you took a one-way cruise from Vancouver to Seward or Whittier (the same 7 days as with the round trips from either Seattle or Vancouver) you could visit either Glacier Bay or Hubbard Glacier on the way up (or down) and also spend a day or two (or, ideally, more) in Southcentral Alaska (Anchorage etc.) during which you could visit Mt. McKinley, the marvelous College Fjord glacier complex, Kenai Fjords National Park, or any number of other places, and still enjoy the Inside Passage and the Southeast Alaska ports of call.

We were lucky enough to get spectacular calving in Glacier bay. No binoculars were necessary to see it, it was amazing to the naked eye. We also went to College Fjord on our cruise, which was good, but nothing compared to Glacier bay.

From a pure scenery standpoint, I think you probably get to see good glaciers from any of those options (Sawyer, Tracy arm, Glacier bay).

It may also depend on time of year...I believe early in the season it can be difficult for the ships to get all the way up Tracy arm, so you may have less chance of seeing the glacier there.

But it is really the calving action that makes it, and I don't know if that is more likely in Glacier Bay than elsewhere. All I can say is I was very glad we made it a priority to get an itinerary that included it.

Glacier Bay a Must! Holland America has the Best Food & Service if you don't mind hanging with senior citizens and dressing-up (mandatory). But seems like everything (including clubs) Closes-Down at 9pm, I guess, due to senior citizens going to bed early and becomes a empty Ghost-ship?
Carnival has much more clubs (much younger crowd) if you like to party all-night, very casual dress and more variety of different food and it's all Free altho food quality not as good as Holland.
Princess mostly mixed crowd with families, couples and senior citizens with 2 formal nights but now charges for ice cream, sushi, & shrimp cocktail. Only 1 dance/disco club. Outdoor Movies under the Stars cancelled due to cold and wet inclement AK weather in May or late Sept.

http://www.alaskapublic.org/2012/12/19/sitkas-dream-line-increases-regional-cruises/

Consider a regional cruise.

We cruised Alaska Inside Passage from Vancouver and loved it all! This included Glacier Bay and I can still see the caving and the stillness and remember the hot spiced wine on deck as we witnessed the beauty. We were with Hal and the shore excursions in the ports were the best we have ever taken.

Buonconvento:

In order to "catch" my 50th state (Alaska), we took a cruise on HAL, even though we are decidedly not cruise folks..actually fiercely independent travelers worlwide..but the cruise seemed the best way for us to at least see and experience some of SE Alaska's highlights including Glacier Bay. It worked out well for us. We did most of the "options" on our own, taking a local bus to Mendenhall Glacier from Juneau, and doing our own walk through Sitka's colorful totem pole trail, and our own walking tour of Ketchikan..all worked out fine.

Perhaps these pics will give you some familiarization with the HAL cruise and it's stops. Luckily, we had sunshine most every day, aside from Juneau.

Have fun...not able to compare, we found HAL to be a very comfortable choice, fine food offerings, and very large verandah state rooms at a "fair" fare.

I may possibly be traveling on rare occasios as a solo, only domestically and Canada. My dearest wife is now mentally incapacitated. So happy we had done so much wonderful travel over the many decades. Never wait until tomorrow!

Have fun, BC..it's an excellent itinerary (also roundtrip, Seattle to SE Juneau, Glacier Bay, Sitka and Ketchikan with a short stop in Vistoria).

Stu Tower

Below are some selected photos with an overdone ton of Glacier Bay. (I'll try this method first..if not, I'll re-issue)

2010 Alaska, Juneau & Glacier Bay

2010 Alaska, Sitka - stu - Picasa Web Albums

2010 Alaska, Ketchikan - stu - Picasa Web Al

BC..didn't work..these should:

https://picasaweb.google.com/stuarttower/Alaska2010JuneauAndGlacierBay#

https://picasaweb.google.com/stuarttower/2010AlaskaSitka#

https://picasaweb.google.com/stuarttower/2010AlaskaKetchi

BC...sorry about Ketchikan, I re-copied:

https://picasaweb.google.com/stuarttower/2010AlaskaKetchikan#

Tower,
Enjoyed your photos of Glacier Bay. I've been to Kenai Fjords. Hope to get back to Alaska soon.