web wallets can be hacked and it can be done by hackers by many ways as they can send a phishing link or a key-logger to your system through third party software downloads etc. but hardware wallets are fully safe from these vulnerabilities so i am in favor of always using hardware wallets.
Your list have many good altcoins with big growth potential and i also hold many coins of this list. This is the best site to hold and start accumulating as market is showing revival signs and altcoins will give more returns rather then holding bitcoin in those circumstances.
Now the market showing revival and bitcoin and ethereum both are showing some strength and it shows that bull run is ready to start anytime from now and the market will start follow it after its confirmation.