I’ve been to almost every city on this post (so far) and I’ve gotta say Montreal. Accessible. Safe. Cultured. Everyone is inexplicably attractive. Everyone is nice. There is a scene for every taste.
Budapest. It’s beautiful and full of great history.
Seville, Spain is pretty high up there.
Quebec in winter. Basically any North East Canadian city. Magical.
Washington, DC. So much cool stuff to do for free.