I should add that I am from Hong Kong, so Cantonese is my primary language. Maybe the tailors will better understand what I want?
Even if you speak the same language, communicating what you want to a tailor is a language skill you only learn with experience.
Custom clothing has a learning curve. At the start, you only know what you don't want when you get it. Some things can be corrected over the course of fittings (if you get them) but some cannot.
If you have the money and you need clothes, and you're in NYC, why not make the bespoke stuff the thin end of the wedge. Get RTW mostly, and commission one piece or two from someone to begin a relationship.