Nope, most enemies don't scale with you. It's great.
The reason ranger vets are so difficult is that they have heavy armor and good guns. Going along with that, the change to the armor system (DT as opposed to DR) means that heavily armored enemies became much more threatening and difficult. As they should be.
I just entered the Hidden Valley bunker with my new explosives character and Living Anatomy shows that the BoS Paladin's HP has increased from 125 to 165. From what I've seen so far, their maximum DT is 31. Their HP should be much higher though.
I understand what your saying.. it just feels weird after playing fallout 3 and having such a powerful way to deal with enemies in your hands only to have it reduced in New Vegas. VATS is to fallout as Bullet Time is to Max Payne. .. if they mess around too much with bullet time for Max Payne 3 it's really going to feel weird. But.. if you think about it... This game will be able to take you to level 50 by the end of it all. We'll have the choice to pick almost as many perks as in fallout 3 and have almost twice as many hp's by the end. Plus we have the added perks from doing the challenges.. and they aren't even optional.. Your going to be a god by the end of this game and .. if you take a high agility, take a couple action boy/girl perks.. you'll have enough ap's to beat what you need to in VATS. In fact you can get more AP in Fallout New Vegas than you can in Fallout 3 I think.. Agility at 10 nets you 95 ap, Take the Kamikaze trait gives you an extra 10, Take two levels of Action Boy for 30,, Where General Olivers Uniform for 20 more.. Take an Ultra Jet for 40 and you have 195 AP.. .. That's quite a bit of ap.
They should adopt the "Evasion" derived statistic from Van Buren which would make the combat a lot more challenging and less predictable and simplistic.