Is On Hit Kennen Top op?

i've been wanting to add him to my champ roster, but i would rather not put him in if he's just going to get nerfed quickly, i just got burned by the maokai rework and the nautilus nerf right before all the tank item changes made him way weaker, so it really would be a deal braker if he ends up in the patch notes to quickly. Any thoughts? Also if you have a suggestion for any split pushing champ(mobile one is my go to if their team comp allows me to split push without needing to escape to often) it would be greatly appreciated.