Maureen
I have been to New York twice with JY, and I have also travelled with family to New York so any questions just ask, I have seen and done many things in New York and I was there for a Week this year.
Re dress code I cannot imagine there being a dress code, USA is rather relaxed on dress and who wears what etc.
I have travelled the world with JY and I always go for comfort, there are long flights and coach journeys, smart casual is my wardrobe, and comfy shoes are a must. You might want to stick in some gloves and a scarf just in case. On all the USA tours I have done which are many the tour manager has travelled with the tour group other than the Florida one I did and she lived in the states and met us there.
Cindy