Lately a new "Exchange 2.0" taking over. Bittrex & Polo suffer from many complains, locking accounts and many other issues.
Kucoin & Binance are quite different. they have their own token which give benefits.
Both are going very big in Asia and International.
Check out how Kucoin perform vs other exchanges:
https://www.kucoin.network/Your opinion?
I heard kucoin just recently, I think it was less than a month ago actually I made an account to this new exchange platform then when I open it the interface was quite good however even I'm not quite familiar with this exchange but I feel it will become like bittrex or poloniex someday.