Tough choice; both great ships and good itineraries. I guess it's no secret here that I'm a Princess fan. But I have a couple of good friends whose judgment I trust tell me they loved Norwegian Star. And it looked very nice from their photos.
I think Victoria is a much better choice than Prince Rupert. And the Princess itinerary gives you more time in Juneau and Skagway. So I would have to say I prefer the Princess itinerary.
I have absolutely nothing against NCL or Noregian Star, but after 30+ years of satisfaction with Princess, I think you know which ship I recommend. My wife was on Golden Princess recently and said everything was as great as it has always been.
So either ship will give you a wonderful cruise, but I see some definite advantages in the Princess itinerary.
Hope this helps a little. Please stay in touch and let us know what you decide; or we're here if you have any more questions.