You are right. Most exchanges are still work in progress and they keep improving themselves by the day. Having said that, I find Binance quite okay. The interface is not pretty, but it works and they have many alcoins available for exchange - so you'll most likely find the smaller ones in there. Also, because it is not a big exchange, they tend to have better customer support (e.g.less queries).
I haven't used Poloniex, but I've heard some good reviews too.
RE: Can We Talk About Penny-Altcoins Yet?