There's something immensely satisfying about being an unarmed badass. And I don't mean your fancy pants kung fu and whatnot. I mean settling your problems with only your fists. Any punk can shoot a gun or a laser from across the room, but it takes a man to get close enough to his enemies to make them explode in a cloud of bloody giblets with his fists. Unlike Skyrim, an unarmed badass build is not only viable in FNV, it's insanely overpowered if you select the right perks. Bethesda should be paying me a commission for my Skyrim and Fallout builds. My game playing genius and incomparable prose have no doubt compelled hundreds to go out and buy these games.
The one drawback to an unarmed badass build is that it requires investing heavily into a second attack skill: melee. You might think that melee and unarmed go together like peas and carrots, but you would think wrong. Melee weapons have terrible critical damage. The best melee weapons, i.e. Oh Baby! and the chainsaw, cannot deal critical hits at all (which is fine since their base damage is so high anyway.) In contrast, critical hits are your bread and butter with an unarmed build. That means you want high endurance and high luck. My SPECIAL stats for my first unarmed guy:
S - 6
P - 5
E - 8
C - 1
I - 6
A - 6
If you want you can take one or two points out of intelligence and make luck even higher. It's best to never take intelligence below four, which is the minimum for the Educated perk (although role playing an idiot Courier with an intelligence of 3 or below leads to some hilarious dialogue options.) Strength is at 6 because one implant and the Reinforced Spine perk from Old World Blues will put it at 9, enabling you to use the holy grail of unarmed weapons, the Ballistic Fist. Agility is at 6 so the implant will qualify you for the Slayer perk. Perception is at 5 so that the implant will raise it to 6 for the Better Criticals perk.
Tagging skills at the start won't make or break your build as there are more than enough skill points to max out all but a few skills before the end. And it's a tough choice. I ended up tagging Unarmed, Melee, and Repair and I'll show you why below with my perk plan:
Level 2 - Light Touch (requires a repair skill of 45, but adds 5% to your critical chance when you wear light armor. Crits, crits, crits... always increase them.)
Level 4 - Educated
Level 6 - Toughness I or Bloody Mess
Level 8 - Super Slam! (requires 6 Strength and Melee 45)
Level 10 - Finesse
Level 12 - Piercing Strike (this perk pretty much turns you into a Deathclaw)
Level 14 - Jury Rigging (Repair 90 - a steep cost, but worth it in the long run)
Level 16 - Better Criticals (Perception 6, Agility 6 - must have)
Level 18 - Paralyzing Palm
Level 20 - Ninja (Sneak 80, Melee 80. It's bugged in that it multiplies your crit chance by 1.15% instead of adding a flat 15%, but anything that increases crit chance is worth taking)
Level 22 - Toughness
Level 24 - Slayer
And the rest is up to you. My unarmed badass was a Wild Card. He's generally a good guy but he has a problem with authority and doesn't like seeing innocent folk getting pushed around. He slaughtered Joe Cobb's gang in Good Springs with only a broad machete. Once he stole a pair of spiked knuckles from the Primm casino, he and ED-E went to the local prison and slaughtered the Powder Gangers to the last man using only his fists. I should have named him Logan.