Centralized i prefer kucoin and binance.
But decentralized not very good options. I use forkdelta or idex (which is not compeletly decentralized)
forkdelta too low tokens price. And on the stock exchange idex the minimum amount of a transaction is 0.15 ethereum, this is not very convenient when you receive small rewards for bounty.
On Forkdelta too low token prices cause bounty hunters dump prices and that is because project developers do not lock tokens before they list any good exchange . i think this is the main reason.