Corki can have a rumble ult at level 1

But graves can't have a cigar?

Alistar has a Malphite ult at lvl 2 Wukong can have a Shaco ult at lvl 1 Leblanc has a Shaco ult at lvl 1

Corki W = MAGIC DAMAGE PER HALF SECOND: 30 / 45 / 60 / 75 / 90 (+ 20% AP) Corki dashes to the target location, dropping bombs that leave up to 4 blazing patches along his path, depending on the distance traveled. The fire lasts for 2 seconds, dealing magic damage to enemies that remain in the area every half-second, for a maximum of 5 ticks of damage. Rumble R = MAGIC DAMAGE PER SECOND: 130 / 185 / 240 (+ 30% AP) Rumble calls down a line of rockets down the target path which remains for 5 seconds, dealing magic damage every second to all enemies within and slowing them by 35%. The Equalizer can be fired in any direction in any point from any point within range.

Level 1 Corki can only have 1 point in W and if someone stands in it for 2 seconds they only take 150 damage. Level 6 Rumble can only have 1 point in W and if someone stands in it for 5 seconds they take 650 damage.

These are just the base damages. The main difference here is, if someone sits around in Corki's W and doesn't run out of it they aren't paying attention because this doesn't slow people in the fire. If someone stands in Rumble's R and doesn't run out of it, it is because they are slowed and can't leave within 2 seconds.

It's pretty balanced, even if they are 5 levels apart. Corki's W on a full duration only ticks slightly more than 1 tick of Rumble's R.

Also he gets a free dash with it so it's better!

I admit I down voted this when I saw it, but then I realized this was "memes and games" and rescinded my down vote.