Pushing is supposed to cause enemies to divide their attention to you. And it does work a little bit, but not for long enough.
I recently had an experience with a skaven horde where I’ve shoved them all down to the ground with a shield. When they stood back up I went out of attack range for some of them, but those few just decided to path to the next closest party member. Who was much farther away from them than I was. It didn’t really make sense.
I’ve had the same problem often with Chaos Warriors. For example, while staggering a Chaos Warrior with constant pushes, they can easily change their target from me to another teammate who was causing some damage and make a 180 turn and swipe at the teammate. Making me, the tank, kind of useless. Even when I was making a hard effort to distract the CW.
It seems like the effects of pushing gets overruled too easily. I can’t really assume what the algorithm is for targeting is. But it’s like pushing just times out very quickly, or it doesn’t matter because the slightest damage was taken from someone else.
My suggestion is to just make it a rule that pushing overrules an enemy’s targeting choice for a longer period of time, no matter what else happens to them besides another push. Even if the aggravator moves out of range, he should be followed. It could be done that push-strength determines the amount of time the opponent is aggravated, with shields having the longest and best effect. While a one-handed weapon has the worst.
I think that most mobs must have some kind of threat table, with the strongest factor being proximity and available slots. Pushes must just generate a burst of threat, but not enough to necessarily beat out “available slots” or something.
Pushing to get aggro is a bit less noticeable in this game than the first, since most enemies seem to get blown through relatively quickly, or are still a threat when you’re not the main target (ie, swipes on elites).
I suspect pushing to get aggro is more tied to stagger than pushing by itself. This would mean that the push strength reductions also reduced the control capability of shields, but I doubt that’s a big issue - shield push is still a strong stagger. More likely is that, as @BizarreSalp suggested, there are threat priorities at play, and that stagger is fairly low on that list.
Positioning and available slots are likely to be high on the list, but it seems that also damage is higher than stagger, so someone doing a small amount of damage gets the aggro easier than another staggering moderately. Boss behavior at least suggests this, as the highly damaging Careers will get aggro quite easily, even if someone else is constantly dancing with the Boss and doing a steady stream of damage (and stagger).
There also seem to be slight differences on different enemies, but that may be just due to different armor classes reacting differently to both damage and stagger.
With all that said, shields certainly do seem to be intended as control tools in the game. While they do work at that role, they miss out on other (arguably more important) aspects, and unlike in reality aren’t really that good on defense (mostly because blocking is usually a secondary defense method here, and doesn’t work on everything). I think they still need something a bit more to be on the level with other weapons. A suggestion that has been presented before is that there would be a Weapon Special action that would only pull enemies’ attention. Once again, it wouldn’t need to be a strong effect, or last long (even if it just “stunned” enemies for a moment, it would be helpful), but it would certainly give shields something unique. It would also give us more use fro the Weapons Special, something very much underused still (and because it’s underused, there aren’t many chances to learn to use it effectively).
Now that is a cool idea. Clang your weapon against your shield to draw the attention of enemies that are nearby, but not ridiculously far away. Or even if you do it enough, you distract bosses. I’m 100% behind this.