All the action is like the OP said, in San Nicolas (St Nicks), every brothel looks like a small strip club.
Here is how it works in St Nicks. You either drive or rent a cab from the hotel district, if cabbing it be sure to have the driver stay with you as it can take a good hour to get another cab to come get you when you want to leave. There are literally dozens of small strip club along their little strip, each one is licensed for four "dancers" with the exception of one, if my memory serves me right it's called Chesterfield's has eight.
In each club you will find one chica dancing, just like any other SC, with the other girls working the bar, if you find one you like you pay a "house fee" of about eight bucks, and then the chica gets $30-40k for a 20-30 minute session. You are free to "re up" for as long as you like of course, the rate is so low you can almost stay overnight there for as cheap as one of the pricey resorts down there, actually there are a lot of rooms that go for around a grand a night in Aruba so your play time is going to seem dirt cheap in comparison.
The chicas rotate every 90 days, but some of the chicas come back on a regular basis.
One thing to keep in mind about St Nicks, it can be dangerous at night, Use serious caution while down there, it's also highly advisable to either have a wing man, or get a reliable cabbie to not only drive you there, but stay with you until you return to the very safe tourist area. Tourists have been known to get mugged and stabbed if you get drunk and or careless. Just like most places though, you can have a great time without incident as long as you pay attention to your surroundings. It may take you a few clubs to find a chica that appeals to you, depending on your taste of course, but there are well over a hundred women working down there at any given time, I am sure you will find at least a few that are right up your alley.
Aruba is hardly a sleepy fishing town, it's full of high end hotels starting at $500 night and going up to over a grand.
and while Bogota is still a great place to go, Caracas has turned into a crime ridded shit hole that I would not advise anyone to travel to, unless they are jumping over to Margarita Island.
The one thing that hasn't changed is that both Venezuela and Colombia are home to some of the most beautiful women on the planet. THAT has not changed at all.