Unfortunately that's just too damned simplistic a model.
Violent crime tends to follow population density as much as anything else. Vermont has a small population widely spread out. Burlington, the largest city in the state, is quite small and mostly oriented around a concentration of colleges in the area and an IBM facility. Otherwise Vermont is largely a rural state. It is quickly converting from a conservative state to a highly liberal one. I would expect gun control laws to start piling up there before too long, just because it's "The right thing to do" among the liberal crowd taking over.
Whenever you stack people up in close proximity, especially when those people are poor and un-educated, you get violence. This is proven throughout history, time and again. Population pressure causes war. So New York, LA, Chicago, Baltimore, etc. are extremely predisposed toward violent crime simply because they have large populations crammed into tight quarters. Now if you can find an example of a state with a high urban population and similar demographics to DC, New York, etc. that have few gun laws and low crime, then you have a good comparison.