Portland
Seattle
DC
Boston
Those are the best that I've been to.
Philadelphia is easily the worst.
It is a beautiful city. My first city and hometown for the very early part of my life. I had always wanted to go to Paris and finally, aged 40, I did. Love that city too. DC reminds me very much of Paris which makes sense since L'Enfant was French. What's great about both those cities is how much atmosphere one can have and how many indoor and outdoor activities are available for FREE.
Last summer, I had the chance to visit Chicago for the first time. (Loved it, but it closes down WAY too early at night.) It reminded me of a mix of DC and NYC. And, oddly enough, the drive into Chicago reminded me of driving into Miami. Where the Port of Miami is the skyline seemed similar.
Love Hamilton, Bermuda, as well, but it's not a city on the same scale. Venice was magical too, but spent less than 24hrs. there, so don't know if it would have grown on me or lessened in stature. I'd love to go back, though.