Good job planner. IMHO fun defined is a night on the town in Puerto Plata. La Canita is one of my favorites, along with Patio de Johnny. I don't even bother with the tourist discos any more. Expensive drinks and American music? I don't need to fly to the carribean for that! My situation is a bit different, first because I'm male, and second because I bring my dance partner with me. If I get a waitress who's a "live wire", I'll usually ask my date if it's OK and dance with her, just for fun and variety. I think your advice about changing partners frequently to avoid giving the wrong impression makes a lot of sense.
I agree with your assessment of Dominican DJs. It seems a lot of them just don't get the concept that their job is to give the people what they want, get them off their chairs and dancing, and then to keep them dancing til they get thirsty and sit down to buy more drinks. I'm not a big fan of the "rotation" at La Canita. I dance primarily to bachata. They play plenty of it there, but it's 5 or six songs in a row. Then they move on to merengue, salsa and reggaeton, and it might be 8 or 10 songs before they play another bachata. I wish they'd mix it up a bit more, but I still like the atmosphere and the cheap Presidentes.