Dave123,
I think coach to Hawaii is 35,000 miles. Without factoring any additional points that may be earned from now until then, I would suggest trying to get 70,000 points into one of your frequent flyer programs. I am not too familiar with AMEX will it allow transfers to UAL or USAIR? I would give one of those airlines all of your amex points and then transfer some of your airline miles through Hilton to make up the difference.
I believe that there are rewards for flying between the islands for 5,000 points, I don't know which thread that discussed that topic, but that might be a good use of some of your orphan airline miles.
Hope that helps.
R