Hey Mason, I can personally vouch for Gemini (being in NY myself). They allow for immediate trading of your ACH deposits, before the money has cleared, which I think is a massive boon to cc-traders.

I haven't had any availability issues with their backend (i.e Coinbase) and their support staff seems responsive to the fact that the trading GUI needs an overhaul (2 separate pages for buying and selling ETH).

Coinbase/Bittrex are licensed to sell/trade cryptocurrency in NY. If you want to put just a little bit of money in and trade on altcoins, have to buy BTC/LTC/ETH on coinbase and move it to bittrex. Minimum wire transfer to bittrex is 10k atm.

I'm not aware of any other exchanges that can trade in NY right now