have you swung a melee weapon before in real life, like maybe a baseball bat? Does swinging the bat happen instantaneously, or do you have to wind up the swing for momentum? Would a bigger, heavier bat be faster or slower to swing?

Souls games have slow melee attacks compared to something like Devil May Cry, but the speed is intended to be more realistic compared to those kinds of speedy action games. Just apply real life logic to it, and it should make more sense. If the weapon you are using is too slow for you, find a smaller, lighter one that would be easier to swing in real life. If starting out as a regular dude and then becoming more powerful is not appealing to you, or if realistic fights are not exciting to you, then maybe the Souls games just aren't your bag.