There is not only 'deflect or hole', it could aswell get dented before you manage to get through. And even if the weapon breaks through and makes a hole, the armor would have still damped the impact. Mainly piercing weapons are more likely to break through armor, because they concentrate all force on one spot. But armor preventing you, to lose your footing or deflect a taunt, sounds really odd. Armor is no exoskeleton, that improves your balance.
As far as I read, D:OS2 is not really different from D:OS2, it's more worse regarding difficulty later on. The start is harder compared to D:OS1 and the difficulty in the endgame only depends on the fact, if you have appropiate level and actual gear for that level. There are no different built sets fpr attribute, because there is only damage possible.
In D:OS1 you could split up your fire power to keep different enemies occupied. If you managed to CC someone, you were able to ignore him for a while, and focus your damage on someone else. In D:OS2 you are more forced to group enemies up and mass-aoe them to get rid of armor of as many as possible. There is never a tension after armor is gone, because your CC can't fail. In D:OS1 CC could always fail so you had to be prepared for that case.