Places I've been to that I would go to again:
Kotor - Spectacular views on the cruise into the port. Unfortunately, we only got to spend three hours there because of a snafu with the boarding gangway as we were leaving Venice which required several hours to fix.
Lisbon - Spent two days there and could spend several more. It feels like a comfortable mid-size city. I never felt crowded or pressured. Many great things to see and do within easy driving distance.
Saint Lucia - The most beautiful island I've ever been to.
Belize - Did a cave tubing excursion here with this guy (
https://www.facebook.com/charliescavetubingtours). He makes sure you beat the "cattle call" tour groups and makes it a personalized experience for you. He took us to an out-of-the-way family restaurant that made burritos that my kids still talk about to this day. I'd go back just for his tour.
Venice - I could go back to Venice and just sit on a hotel balcony and watch the city live. It may have just been the time of year that we went (late March) but it wasn't crowded and it felt very "authentic".
Paris - Was there for three days and there's just so much more that I want to see. Montmartre is gorgeous.
Santorini - I wouldn't mind relaxing for a couple of days in one of the cliffside Oia hotels with a pool that has a great view.
Places I've been to that I could do without:
Rome - It was great to see once but I could do without it.
Mykonos - Tourist trap. Nothing special
Barbados - Flat, boring. Probably didn't help that it rained and I got a little seasick on the catamaran tour.
Puerto Rico - I think their primary import is spray paint.