The problem with 700c is you will probably have to lose the fenders - which is good if you're looking to save weight, but in my opinion it won't look quite as sharp. 650b also wouldn't be a bad choice if you are willing to put the time and money into it, and you could keep the fenders. Brakes would be a good improvement, too.

If I were in your shoes, I would probably just wax the frame, polish the chrome, and ride, adding new tires as necessary. That's what I did with my Triumph, but then again I'm a cheapskate and hardly ride it as is.