First, you can pop out from a wall, and before he manages to click you, hit him in his hand even 3 times. The probablity of him dropping his weapon is high. You could even cripple his arm. To do these, you just need high critical chance and better criticals perk(better rolls, more chance that critical will cause weapon drop/something worse than just some additional damage).
Also, alternatively you can punch him in his head/eyes and, if you are lucky, cause him to knock down or even knock out. VERY LUCKY means insta kill(if you have better criticals), that's not for me though

Also with my older unarmed jinxed character, i caused enemies to critically fail quite frequently. It's very funny and often saves your life.
Another good thing about unarmed is, that you can very quickly come back to fighting and not loose any eq. Well, for trolling purposes. More serious pvp means good armour + psycho + power fist/super sledge but that's not what i'm talking about now.
You don't need high unarmed skill, just about 150% or even less. When you have 6 PE, which you take because you want Better Critials(believe me, you do), even 100% would be enough. That's why you've got points left to spare into FA and Doc.
Etc. etc.