You will definitely enjoy Alaska!
We sailed on the Celebrity Infinity last August/September (over Labor Day) and the weather was wonderful.
Our outside cabin was very, very nice and we were glad we did not opt to upgrade to one with a balcony. These ships have so many wonderful viewing areas and we were never sorry we went with a regular cabin.
But an outside cabin is GREAT. The windows are large and the Inside Passage will give you some wonderful views.
If you are going to be staying in Vancouver, give Priceline.com some consideration in booking your rooms. We stayed at the Hyatt Regency for $69....all taxes included.
We stayed in Whistler, at a resort, for $39 per night. These are all prices for the room-not per person- and included all taxes.
The only regret we had was not booking on the steam train trip. We also heard that the Whale Watching trip was a good one. However, we were just happy to go off on our own and discover the little towns and mingle with the locals. Had a ball....
We wish you a wonderful trip and great experiences!
Carmen in New Mexico....