DC, NYC, Boston area in the US (I'm an east coaster). Other cities, too, just in the right location. Downtown Asheville, Richmond (where I live) is pretty good if you are downtown or in the Fan, although there's no grocery store right downtown. Also Durham and Raleigh have great downtowns. Those are just the places I am familiar with.

I'm considering Europe as well. In general, European countries have much better health care systems than the US. Fortunately for me, I'm an EU citizen so I can just move there without visa worries. So for me, Paris, Nantes, Bordeaux...what wonderful possibilities! Even the small towns have stores downtown and many have train service to other areas.