I also worry about using gift cards to pay for the cruise fare and having outside travel insurance (CC, purchased, etc) reimburse if a cancellation has to be made. Therefore, I purchase the HAL CFAR plan (or Princess CFAR plan for cruises on PCL), and then purchase my AARP gift cards as close to final payment as possible and use them to pay for the cruise fare. In effect, the 10% reduction in the gift cards, pays for the CFAR protection and I have the comfort of knowing that I can cancel, if needed, right up to embarkation day.
In January, my DW and I had to cancel a cruise with Princess that was paid for with AARP gift cards. We had purchased the Princess Platinum plan, which reimburses 100% of the cruise, either as future cruise credits or cash depending on whether or not it was canceled for a certain reason (medical, etc). My father-in-law had open heart surgery with complications. We could have received our reimbursement as cash since it was a covered reason, but to simplify, I just had them reimburse as future cruise credits. We had zero loss. With HAL, we would have had a 10% loss due to their highest level CFAR protection plan only reimbursing 90%. A note here, they do not reimburse back to the gift cards at this point.
BTW, it looks like we are both from Idaho! I am just in the opposite side of the state.