Should SA Kayns Ultimate refresh his E instead of some other benefit?

I experimented a bit with that Champion, and by now I feel that there is never ever a reason to pick Shadow Assassin over Red tanky, basically same dmg dealing super Kayn.

The advantages of SA Kayn just dont feel so great, the extra range on your W sounds good, but nearly never comes to use, because if you assassinale someone, you are most likely in range for a normal W anyway. But the cast time gone rocks. thats a good bonus.

But mostly I feel like, once you attacked and killed one, you are often fucked unless the team just doesnt care. Because now you stand there, no escape, no way to dive into the shadows, you are literally a squishy behind enemy lines with no chance to escape unless the enemy team is stupid.

So I thought, what if, instead of giving him extra range on W, what if SAs Ultimate would reset (or reduce) the Cooldown on his E? That way he would have a chance to escape, but not a get out of jail free card like Zed or LeBlanc, because other than their instand blinks, his E can be interrupted.

BUT you would have a chance, you could get away if you play it right.

I think that would help SA alot, maybe even make him a viable choice even if you dont steamroll the game and even would win with AD Assassin Soraka...