I remember FO3 being very leaned towards guns, most-especially energy weapons at end-game, but it seems reversed in this one. Energy weapons are laughable and burn through ammo like nobody's business, while melee comes quick, easy, and often one-shots most humanoid mobs.
I took out a Feral Ghoul Reaver with a cross and uppercut combo. Those guys used to take entire frenzied firefights, and I just Muhammad Ali'd them. Insane.
But yeah, I'd recommend both. Having a high Unarmed, Melee, and Sneak gets you the BEST melee perks and whatnot. Especially if you have 7 Agility and get Slayer. Bumper Sword madness.