Well written piece. Although Bitmex is the most popular margin trading exchange, I do not belive that it is the most user-friendly. A lot of traders (including me) are turned off by the advanced interface. This is why i like the Delta Exchange, an exchange that is easy to use, and that offers a range of innovative solutions such as automated trading and an option to hold USDT when you aren't certain about the direction of the market.
But don't forget, bitmex is the world's largest digital currency exchange. The depth of the transaction is large enough. This is very powerful. When you enter with a certain amount, other exchanges may not take orders in a short time. But bitmex will.