The combat system was ok-ish. I liked the exploration part the most
What i didn't like in Fallout 3 was :
- With broken steel every mutant you meet after level 8 is an overlord, that takes half a billion head shots to kill
- Why can't i tell the ghoul or the mutant to go into that irradiated chamber!? Nobody would have to DIE.
- Sniper rifle breaks in 10 shots? The **** !? One has to carry twenty of them into the wilderness
Well, there aren't any behemoths or overlords anymore. On the other hand, there definately are highly durable enemies. This particularly being due to damage thresholds, as certain amounts of damage just don't get past certain armour classes, and this often includes the hides of certain enemy types. So this will be particularly true for deathclaws, cazadors and radscorpions unless you throw in a mod or something.
There are 4 possible ways towards an ending - siding with the NCR, the Legion, Mr. House or just doing it yourself (with the help of someone you meet along the way). And none of them have any plot points where you have to sacrifice yourself or any of your companions.
I think things break down much slower in NV, but that might just be me. However, I'm pretty sure it's easier to repair since equipment types don't have to be as exact as they did in FO3. And then there's also the jury-rigging perk, which allows you to repair equipment using even less related equipment. I found finding ammo to be much more of a problem than weapon condition.