For Ketchikan I would suggest the Duck tour. Your daughters will love it, especially if you get them the duck call devices they'll sell you. It's fun for adults too. They do a tour of the town and then drive into the water for a short while. It's a lot of fun. I've never been but a lot of people seem to like the Lumberjack show as well.
You seem to have Juneau and Skagway more than covered for excursions.