Ekko's W

Am I the only one who thinks that Ekko's W is too good while there's only 1 point commited to it and that there is little reason to go further?

Parallel Convergence RANGE: 1600 COST: 30 / 40 / 50 / 60 / 70 Mana COOLDOWN: 22 / 20 / 18 / 16 / 14 Parallel Convergence

Passive: Ekko's basic attacks deal 5%「 (+ 1.81% per 100 AP) 」of target's missing health as bonus magic damage (Capped at 150 vs. minions / monsters) versus targets below 30% of their maximum health.

Active: Ekko calls upon an alternate version of himself that bats a device to the target location. After a total delay of 3 seconds, the device expands into a broad sphere that Slow icon slows enemies by 40%. Enemies do not gain vision of the target area until the last 0.5 seconds.

If Ekko enters the sphere, it detonates, granting him a shield for 2 seconds while Stun icon stunning all enemies inside for 2.25 seconds.

Shield Strength: 150 / 195 / 240 / 285 / 330 (+ 80% AP)

The only things that change when you level are the cost (INCREASING!), cooldown and Shield strength. Other champions also have abilities with little other than CD changing with levelling, but those abilities usually just don't have any other stats to scale with.

Meanwhile, this ability could scale in SLOW, STUN and in DAMAGE of the passive.

I think the mana cost should be a flat 50 and atleast one of the 3 aforementioned should scale with level. For example: Slow: 20/25/30/35/40%, stun 1.5/1.75/2/2.25/2.5 seconds.

Also, +1.81% per 100AP makes little sense as a stat for me.

Note: I'm not saying that this ability is too strong. This thread is about that there is not enoung incentive to put more than one point in it. In terms of diversity and decision making, it's a big 0. (Except for when to put your first point into it). Making it scale better with level could also allow Ekko to have a better lategame while not being oppressive midgame.