which new vegas perks are must picks on a first run?

Educated early, it adds up over the whole game. Comprehension too if you're the type who reads every skill magazine you find. Jury Rigging once your repair is high enough, it lets you fix gear with roughly similar items instead of the exact same one, which saves a ton of hassle. Otherwise pick for your build. Better Criticals is huge if you've got the perception and luck for it. and take Wild Wasteland as a trait on a first run, the weird stuff it adds is half the fun.