I suggest Binance, Bitfinex and Kucoin. Because the circulation is too much. It is traded quickly and conveniently. Security and infrastructure are constantly being innovated. I recommend these exchanges for convenient transfers.
I agree if you recommend binance, until now I think binance is still the best exchange, for bitfinex I think is too expensive, because we need deposite equivalent to $1000 to do trading, it is very high for me, because I am beginner. while kucoin I do not understand the features of this exchange. would you like to explain to me the advantage of kucoin.?