Well, that's not that easy to answer this question. From the one hand, I would prefer to stick to reputable and reliable exchanges like Coinbase, CEX, or Poloniex. But on the other hand, if these exchanges decide to launch their new trading platforms, I am ok with it too. For example, Coinbase and CEX created pretty good new products — Coinbase Pro and CEX.Broker, https://cexbro.com/.