My suggestion is binance. There are a lot of coins here, the biggest volume of transactions. If you hold a large number of coins, it is very convenient to sell here.
Binance is good exchanges everyone accepted but we should choose profitable and promising exchanges so we can pick some other trading site it will make profit. I think many traditional exchanges are really more convenient to sell in the altcoins and many new altcoins are occupy the more space in Binance so we should analyse the best platform then buying or selling the Cryptocurrency.