Just back from similar trip and also stayed in Brooklyn
Some stuff to consider-
Don’t use today tix
We went th theatre box office in person (this was Book of Mormon so high demand show) to buy next day tickets and asked what the best options they could offer were. We got the $220 seats each for $150 each and paid no fees on top. So basically we got better seats for our budget and saved on fees. Also so theatres the cheapest seats are still great others are awful- do resrearch before you go.
Brooklyn- where are you- dumbo/Williamsburg?
We used tube a lot but had most fun at a slightly slower pace using the public transport ferry’s (like the clipper in London)
Super efficient and a free sightsee along the way.
We uber on arrival (JFK) and booked hotel taxi recommendation on way back. Uber was significantly easier and better...
We LOVED Brooklyn (I’ve been to USA before for work a lot so didn’t feel we needed to do too much sightseeing anyway)
Would recommend a day around soho/flatiron - do Chelsea market wander up the high line from start to finish, there is a curvy cool building at the top which name escapes me- book in advance of get tickets for late in day and return
Amazing food markets in Brooklyn on Saturdays and Sundays- location varies in w’burg And dumbo
Sunset from Brooklyn over to island is fab from some of the hotels roof bars you can just buy a drink at
Dumbo has some nice hidden garden roof terrace parks worth just chilling at
We ate seriously well I w’burg- can give you loads of suggestions- and tbh trip advisor served us well too
If your child is 21 and wants to drink they will need ID everywhere always
With poor dollar rate everything seems expensive now, but Brooklyn was a much better vibe than I’ve ever had on island and they were less tops obsessive too (ie obv you tip but weren’t hounded before you’d even paid)
Wear comfy trainers cos you’ll walk miles!
Oh also- if you can pay for fast track, credit card pass or business class tickets for return to get the q jump pass for security at JFK do- we had one of those and it still took 45 min. Without probably 3 hours. Allow ALOT of time. Also check terminal for facilities- that was delta virgin terminal- it’s fab. The BA one is hardly anything so bear that in mind for food!!
Enjoy!