Thanks for all your suggestions so far. I'm probably not your typical traveler in that I don't spend a ton of time looking for tourist attractions. I'd rather be out and among people. This will be my fourth or fifth visit to Singapore (I'm losing count). For some strange reason, I find it eternally fascinating.
It sounds like Hong Kong to me. Phuket is wonderful, but I can't spend that much time on a beach. I get too bored, especially since I stay clear of Patong.