What exchanges are you using? I'm currently using Bitstamp, I have no issues so far, it inspires security to me. However, it only offers a small variety of coins (BTC, ETH, XRP, LTC, LINK, XLM) and a few others, at the same time though, its fees are quite high, at 0.5%.
Looking back and my transaction history, I've spent a respectable amount in fees, which is definitely a waste of money.
I've also used Kraken, but didn't really like its design and layout, I don't remember why I moved my funds to Bitstamp though, long time has passed since then, and I've got no clue.