I agree with Binance at the moment here. I think it is always a good idea to trade on the biggest which is Binance at the present,,, but to always keep an eye out for the status of others. Like investment, I try not to trade at only 1 place, you just never know what can happen and if at least one exchange closes, you have still others to trade at.
Support speed is extremely important for me, also. In case of problems, you do not want to wait for weeks.
When it comes to that of making a choice amongst all the trading exchanges which are there in this world, you will listen so many different names but there is no need to trust on every single name which you hear. I think of bittrex trading exchange to be the best possible option amongst all other exchanges and that you can trust on this exchange without any kind of worries in your mind.