Idea for Clarity change to bring it back to SR

I was just looking at all the summoners and thinking about how they've become game-mode restricted (many for good reason) when I had an idea to make an interesting summoner for SR. What if, like how heal got a speed boost attached, Clarity got a slow attached? It would just be a minor one, and my idea for application would give it some decent counterplay.

The way I imagine it would be that it would empower your next spell to slow enemy champions hit by it. This would just be a one instance slow, so dots would not get extra benefit from it, and since it is tied directly to the next spell of yours, it could potentially be dodged.

My idea sprouted from Clarity being so similar to how Heal used to be (hits everyone in an aoe with no secondary effect). Once heal got changed to provide a bit more utility and be more focused (stronger but on only 2 units), it became an incredibly valuable summoner. Similarly, if Clarity was given some extra utility (and likely restricted down to only affecting you and perhaps one ally), I could see it becoming more popular as well.

The aspect I most like about this change would be that it accentuates what the typical user of clarity (mage or support) does, combo abilities. The slow would potentially enable an easier to land combo after the first ability hits, and the mana restore would ensure you're able to cast the full combo.

I also don't think it would be an issue with assassins and such because its only advantage over exhaust would be the mana gain and the possibility of applying the slow from a greater range.

I don't have any set numbers, but that all could be adjusted fairly easily to find the right balance (mana restore and slow strength/duration).

TLDR: Give it a weak slow on first spell cast and make it only affect the user (and perhaps one ally).