Graves Smoke Screen

I really don't see how Smoke Screen fits into Graves's kit. Here is how LoLWiki describes this ability.

>Smokey Screen ------ Range 950/250 ----- cost 70/75/80/85/90 Mana ------- Cooldown 26/24/22/20/18 > Active: Graves fires a smoke canister at the target area, dealing magic damage to all nearby enemies and briefly slowing them upon impact, and creating a cloud of smoke for 4 seconds that applies nearsight of outside the area to all enemies within.

>Magic Damage 60/110/160/210/260 ( + 60% AP )
Slow 15/20/25/30/35%

It is a decent amount of damage and a slow, and limiting the enemies vision is a great idea. In my experience this is actually a fairly difficult ability to land. I am not a Graves veteran so I imagine that with practice I could get better, but ultimately the slow is not all that strong and hampering your enemies vision doesn't really help all that much unless you are trying to temporarily blind someone so you can try to get away with a dash or flash, which is a little strange to me because it really seems to me like Graves is strongest up close. As for the damage, the base numbers are decent, but I feel that is because most Graves builds do not involve AP. I have tried AP Graves, and it was garbage. The cooldown is simply too long and the utility of this ability is simply not there. I honestly think that this ability could be completely replaced by something that fits him more. If not, I feel that it should either scale on something that Graves actually uses. I would actually prefer to see the slow scale with a stat or simply have it slow with AP as well.

I expect that some people will disagree, if so, please let me know how you feel it is strong. Maybe you know of a better way that I should be using this ability, please share.