Benefits of generate address from sha256 hash than random address
Generating from the hash of a string is known as a Brainwallet. This has the advantage that it is potentially easier to remember and recreate your wallet if you lose the keys.

This also have the disadvantage that people are terrible at picking entropy, and it is trivial to crack most brainwallets via brute force. You have far more security relying on randomized generator than more or less any brainwallet you could come up with.