Maybe for a new trader you can try hitbtc, because there is very easy and there are many traders who play there. If you are already proficient, I think poloniex is one good exchange.
I don't think that hitbtc is such a good option because I remember when they are always disabling the withdrawal button making so many people worry about their funds, if I were to choose I'd simply go to binance.
If you are trader, it is always better to choose exchanges that have quite of daily trading volume so that the activity can go faster, not just waiting for buy or sell orders.