Of the cities I've visited: Home (Pittsburgh) and Paris. I don't understand why people live somewhere if it's not on top of their list of places to visit. I really enjoyed Las Vegas too (I got married there!) but I think it's not for everyone.

As per the original question, I'm a cost-conscious traveller and I'd tell the person to go as far as they can on that free ticket

Of the cities I've not visited: I'm most excited about going to London and Sydney. Have plans to burn a lot of miles to get to Sydney