hand weapon does slightly more damage than before (not much) and many enemies now have reduced damage mitigation, so it is more efficient than it was even not taking into account the shield.
hand weapon also has an added advantage to consider, compared to light weapons: higher damage means you can surpass armor more often. Even if a faster weapon can hit more often, against a highly armored and shielded opponent, the "real" DPS will be much lower, because armor is subtracted from every hit.
Example, to make my point. Imagine two weapons, one hits for 15 each second, another hits for 20 every 2 seconds. Obviously the faster one has a much better DPS.
Now use it on a shielded enemy with armor 20 (negates 8-20 from each hit). The fast weapon is going to hit for minimum damage almost all the time, and will likely do much less damage than the slow one.
So against a highly armored single enemy, 2 handed is great, followed by hand weapon.
Additionally a new mechanic is going to be introduced soon which will favor slower weapons against certain (special) enemies. Can't say more at this point.