The game has an odd asymmetry between elemental disabling of foes and physical disabling. Elemental disabling always requires at least two attacks from zero armor (one of them can be the attack that reduces to zero armor), or requires something else to be true: e.g. wet status. On dry ground without bleeding, you can't go from normal to stunned.
But for physical damage there's no intermediate step: once the armor is reduced, knockdown is possible. And knockdown is OP. A lot of builds would be more challenging if battle stomp only throws enemies "off-balance" when reducing their physical armor to zero. Or if knockdown didn't completely disable, but reduced AP after "getting up." Something along those lines.
Knockdown arrows should not exist. I know they were in DOS1 but come on. And there should be finesse weapons that are elemental in nature, allowing finesse characters to complements mages and not only complement warriors.