I like Binance. easy to use. However, if they can add more coins like STEEM that will be great. Besides, wouldn't it be better if sopt-limit is base on usd not btc because btc value changes, it's hard

Coinbase does have high transaction fee. You can use Gdax to avoid transaction fees. You can either deposit cash or BTC/ETH/LTC to Gdax and use Gdax to send your coins to a some other platform. Besides,