I'm getting a bit concerned though about XRP's current giddy price. Low fee or not, it will be painful if its value sees a drop that's as sharp as the rise.
But anyway, concerning transfer fees from exchanges - generally, Bittrex is reasonable enough. Except for BTC. With this one, I've learned only today that Poloniex's rate is great. Unfortunately, not so for its ETH fee. So, we'll have to shop around to see which exchange is cheaper/cheapest with each of our favourite coins.
Binance's transfer fees suck the most. Especially for ERC20 coins. Some are just plain blood-sucking. However, I'm using it because it has many of the new, hot coins and tokens that are not available at Bittrex and Poloniex. Have to live with this evil, I guess. Grudgingly.