If it had AP+ it's current stats(Could even remove 50-100 health, all of the heal regen) I would most certainly pick it up on Diana occasionally.
It'd be my rush item sometimes Vs AD champs. The active would allow me to make the dives that are so often terrible ideas on early Diana(They're just so fun though), while the health/armor would help me.. Y'know.. Not die to the AD enemy. Adding AP would allow me to not only not die, but also retaliate and actually deal some damage - Opening the window for the aforementioned dive.
That said, I don't think it should have AP. It honestly has very little reason to even exist these days overall. I'd rather see it as a tank item with +armor, +health, -20% Damage from towers(Only towers) and the active changed to "Forces selected tower to target the Ohmwrecker user for x seconds(or until user leaves tower range)" - Making it an item that you could use to save allies when they draw tower agro. Using the active would force the tower to target you, and you'd have that little extra defense from the tower damage reduction. Would be useful when you're playing your tank of choice(Let's say Malph.) and can't QUITE keep up with the carry in front of you(Let's say Diana) as you both chase the near dead enemy(Die, Annie!) - Your carry dives, gets the kill, eats a tower shot - You walk under the tower, use the active, and it targets you instead so that your carry can safely escape before they take the 2nd/3rd shot that would have killed them.
Would also then be useful in teamfights under the enemy tower if the tank doesn't land the first hit to attract agro. Not every tank can get in there faster than their carries(And not every carry is patient.), this would allow them to over-rule the typical priority, and take the agro in the middle of the teamfight.