From a former gigging NYC-er: Regardless of what you go with, a pair of corner casters and a telescoping luggage-style handle will make your life exponentially easier. (Like these: http://www.markertek.com/Audio-Equip...M-W8375K.xhtml
I would start by looking at 1x15 neo combos like the ones mentioned above (Genz Benz makes a really nice one, too) and retrofit whatever you get with the aforementioned casters/handle.
If you're not dead set on a combo (or have a cab that you already like) you can do the above with a cab and pair it with one of the many vertebrae-friendly micro heads out there.
Just my $0.02. Either way, good luck in your quest. NYC ain't the easiest place on Earth to be a bassist.