Why does Aatrox only have 2 charges for Umbral Dash?

Looking at Q and how you need to use both Q and E to ensure that you're going to land it it makes me wonder shouldn't there be 3 charges instead of two?

Or at the very least he would need a lower cooldown for his E active, considering his other abilities also have a long cooldown of 16 to 20 seconds.

Personally I would of prefered something like this...

###E: Umbral Dash

• Cooldown: N/A
• Recharge Time: 3 / 2.5 / 2 / 1.5 / 1 Second/s
• Charges: 3

So the reasoning behind these proposed changes of mine is that, I don't see the reason behind having a such a massive cooldown of 20 seconds for an ability that isn't that impactful. Since it only grants bonus Attack Damage for 1.5 seconds, and dashes the lowest distance in the game.

###What does everyone else think?