One of easiest way to create and access Ethereum and erc20 token is MEW web interface. My question is , is it safe to keep big amount in MEW or better not to rely on it.
If you know how to use it safely MEW then it's safe. I am using MEW since the beginning of my journey in the crypto industries. It's still fine to me, not yet faced any critical issue with MEW. You just need to store the key in a safe place. It would be nice if you not store your key online. Also when you are tried to log in to your wallet, try to use a fresh browser. Fresh means private window, when no addon activated. A few years ago a lot of people lost their funds because a VPN read their private key.