We have taken three cruises to Alaska with
DCL, all in mid August, and we thought the weather was overall fabulous. Of course, we had some rain and bad days, but I'd go again that time of year in a heartbeat. If you are looking for an excursion to see bears, I highly recommmend the Neets Bay Bear Watch By Floatplane - we got some great up close and personal photos of black bears. Alternatively, if you are looking for something very unique, Ketchikan also has the Mountain Point Snorkeling which was amazingly fun!
As far as cabins go, we love the Navigators Verandah category 7a - the balconies are enclosed so you have some extra protection on the sides from the chilly air. Port or starboard doesn't really matter, but I prefer aft because it's a quick hop up to the drink station.
I have a trip report from our last cruise, adults only if you are interested in reading:
http://www.disboards.com/threads/to...-wonder-with-four-adults-august-2016.3560012/
Hope this helps!
Aby