Since you exclude Binance which is practically I've been using and nothing else then perhaps I will only provide how I am choosing a platform where to exchange. Usually, I choose the exchanges who provides the top quality of security, if it is reputable, and the volume because you can already tell if the exchanges are good if it has a high volume. And based on what I have searched in CMC they provided a list of top exchanges, of course, Binance got the top spot and under it, Huobi got the 2nd spot so I would recommend it. Besides, I hear a lot of positive feedback towards Kraken and Coinbase Pro so you could also check them out.