While shapeshift is 100% decentral, then most or all others you mention are centralized and can be compromised one way or the other.
You "forgot" the most important exchange for safe exchange of coins: Bitshares.org , 100% decentral, your coins are not at risk at any point.
For-instance @tatianamoroz got locked up most of her Steem on Poloniex for 3 weeks now and that can happen at any centralized exchange.
I have myself been bad at using Bitshares/ledger, but I found it to be the best exchange we have and I will try to use it always from now on.
Keep it up @heiditravels and I apologize for any inconvenience in the past ... crypto life is not easy for all... but things are better now, thanks for everything at steemy....
L
Yes I clarified this in the very beginning of this post. And I also mentioned I'll be making a list of decentralized exchanges soon to come ;)