The hard part to a melee character is that you must wear light armor if you wish to close in on enemies fast enough that their guns won’t tear you to shreds but when forced into a heads up battle against multiple foes with guns light armor won’t help you too much.
Many of the enemies are stronger and more dangerous in melee than you are, so it’s a risk every time you get near them also, Deathclaws. A melee character is definitely a heck of a challenge in the Fallout games.