I have mostly stayed in Antwerp on repeated trips to Belgium. Other posters have noted that Ghent has more to do after business hours than Bruges. There's no denying the attractiveness of Bruges, but I wouldn't want to waste a night sleeping there.
Antwerp is much larger than Bruges or Ghent, but that means it has a lot more variety. There's a charming more-or-less medieval section, a student district, redeveloped areas, Art Deco/Nouveau neighborhoods, an opera house, many kinds of parks, a nice culture of evening walks, food of every kind and price, and hotels of every kind and price. There's good tram coverage of the city, and a nice riverwalk (and under the river pedestrian tunnel, an unusual sight.) It is true that Antwerp has some of Amsterdam's urban ills, but it's actually cleaner and less crowded. What urban center doesn't have ills?
The only downside to your plan can be the long line to purchase daily train tickets from a live agent with American credit cards or cash. That's the same in every city.
The reason for leaving out Brussels (which does have some nice architecture) is that you only have three nights, and you don't care for museums, which are world-class in Brussels. It doesn't really merit your specific itinerary.