Whilst I have never lived in Santo Domingo, and have only stayed on vacation for a maximum of 3 months at a time, all my family does live there, and I visit twice a year so I think I have some sort of grasp of the city.
Like the OP I'm from New York Cty, and grew up in the hood (Harlem on 113th Street between 6th and 7th avenue) I could remember growing up and not venturing upwards towards St. Nicholas Avenue or Fredrick Douglass Blvd because after 6 PM those two zones turned into a warzone between the rival gangs, and drug dealers. I also couldn't venture east toward 5th Avenue because I'd have to cut through two different project houses in the King towers, and Taft which at one point or another sometime in the 90's rated as two of the most violent housing projects in Manhattan only behind places like the Polo Grounds, and Wagner. I also lived in Brooklyn very briefly in Brownsville in the Tilden Projects, and what I saw, and experienced there for the brief time while I was staying there is 100x worse than anything I have seen in Santo Domingo (again I'm comparing two small sample sizes) While in East New York, I witnessed several people getting cut in the face, I saw 3 people on 3 different occasions shot, I heard 2 different rapes go on as they happened. It was another world out there, something I never knew could exist, but I have also been to places in the Mid-West, and the west coast like LA, and Detroit, where things are soooo much worse than East New York.
So I could understand the OP's point in that being street smart, and from a place like East New York would not make him to afraid of Santo Domingo, but I do think Santo Domingo is an extremely dangerous place. From my experiences in New York, it was always a case of wrong place, at the wrong time. If you don't want to be mugged at gunpoint then don't walk through the projects at 2:00 AM, if you don't want to get jumped in front of the bodega then don't wear all blue clothes in a heavily infested Blood neighborhood, if you don't want to get a buck 50, then don't walk around on Halloween at 10:00 PM in the hood when it is wildly known as gang initiation night. I have never felt unsafe walking down the streets of Harlem or East New York at 3:00 PM, and if I did I was doing something I shouldn't have been doing. There are unwritten "rules" you have to follow in these places, and if you stick to them you're going to be fine, but that's the difference between Santo Domingo, and places like New York IMO there are no "rules" in Santo Domingo.
In Santo Domingo every crime is a crime of opportunity, and the opportunity is when you're not on your guard. In Harlem I have no problem walking down the street listening to my iPhone, and whistling Dixie, in Santo Domingo I would never dare to do this. Santo Domingo people just don't give a F*** what time it is, where it is, whose around. If a crime can be committed it will be. There are no cases of wrong place, at the wrong time, it is just a case of crossing path with someone who just doesn't care. From my experience of course.
I think CC was most on point with his analysis on the crime situation here.