1. If you're going to deposit a big amounts, deposit them in small portions as exchanges have deposit (technical) issues so If for some reason the deposit didn't go through, you won't lose everything.
2. Always withdraw your funds as soon as you finish trading, exchanges can close your account and enforce KYC/AML verification without prior notice.
3. Always take a backup of your 2FA. An exchange may not be able to help you If you lose it.
And no, just because an exchange is charging higher fees, doesn't mean that It's more secure or safer.
Especially this. HitBTC charges astronomical amounts for deposits and withdrawals and while they are a decent exchange, they certainly aren't the best around. Compare that with the likes of Kucoin and Binance who had a 50k satoshi withdrawal fee, and you can clearly see that statement is nowhere close to being true.
Yeah, some of the fees you have to deal with on HitBTC are crazy. Also the gradient of denominations they let you make trades with is really high. Like 0.01 or even 0.001 BTC increments is wildly high. I don't know if they still have that but it's a lot.