Etherdelta exchange compromise last year caused the lost of confidence of traders, so they seek alternative in folkdelta.Folkdelta came around that time also, it wasnt difficult as option. Now there are more decentralized exchanges that service better.
Soon these two exchanges will be dominated by Binance DEX once it's launch, the confidence of the people is high if we talk about Binance.
These two exchanges are the most popular now, I used both but lately I'm using ForkDelta if I try to buy some cheap tokens.
There is nothing to improve in the interface as simple is better, but the security has to be improve.