Personally based on what you are describing I think you as a couple are a perfect couple for a Holland America Cruise. I think you would feel most comfortable with there vessels and the adult oriented activities including culinary sessions, art and wine as well as the onboard naturalists. I highly recommend a southbound itinerary and you may want to spend a few days in Alaska on land prior to the trip. A professional travel counselor can help you find the best deals and there are many in the state of North Carolina. Glacier Bay and an Inside Passage Cruise is what to look for. I recommend the Statendam or Veendam as the vessel of choice. I do not recommend you embark around the 4th of July due to family vacations (kids) however you may not be aware that if you are doing a land based addition that actually late August is a great time to see wildlife.