I spent a week in Santo Domingo a few years ago, and I loved it. I do not speak any Spanish, and that was a bit of a challenge sometimes; but mostly it was fine. Remember that lots of Dominicans travel back and forth to NY, so a fair number of people speak some English. I never felt unsafe walking around, but I am a fairly cautious person and probably avoided anything risky without even thinking about it. I went out to two gay bars while I was there, both fine, neither of them anything special. Dominican men are very handsome and sexy; I was in heaven just looking.
You have to leave town to go to the beach, I think. I spent a day at Boca Chica, which is not far from SD, not at all glamorous, and quite cheap - lots of budget hotels aimed at European travelers. Boca Chica is where I experienced the only really bad thing about the trip: endless hawkers walking the beach, constantly trying to sell you something. I got that a little bit in the city, with tour guides and vendors aggressively offering their goods and services. But at Boca Chica it was nonstop, including many prostitutes (only women, unfortunately). The only way to avoid that is to make arrangements to spend the day at a hotel with an enclosed beach - it does not fend off all the vendors, but cuts down on the traffic a bit.
I did not have sex while I was in Santo Domingo, although I was approached a couple of times on the street in SD by guys who were clearly available for the right price. I was staying in a place where it would have been awkward to bring someone back to my room. A week is probably too long to stay there, but I definitely recommend it if you're looking for something a bit more adventurous than the typical resort vacation. There are caves with cave paintings not far outside of town; I would love to get to see them sometime (and I would definitely hire a guide for something like that).
Ichabod