Janna's "W" Rework Suggestion

I just came up with this crazy idea out of nowhere, and wanted to share it with you guys. It may be a bit broken in teamfights, and a bit useless in laning phase, I don't really know haha. Just tell me what you think :)

Current Passive (And the one I want): Janna gains 9/11/13/15/17% (+2% AP) movement speed and enables herself to pass through units. This is brilliant for roaming across the map.

Current W Active: A point and click ability which slows an enemy champion by 24/28/32/36/40% (+6% AP) for 3 seconds and deals 60/115/170/225/280 (+ frickin' 50% AP) magic damage. The damage is pretty big for a passive support like Janna, and the slow is strong. However it can only target one enemy champion. (Passive is lost when this ability is on cooldown.)

My W Rework Suggestion: A skillshot which grants allies inside it a 10/15/20/25/30% movement speed boost for 3 seconds. Enemies that gets hit have their movement speed reduced by 10/15/20/25/30% for 3 seconds. The ability deals a very small amount of magic damage (50/70/90/110/130), does not scale with AP or anything else and has a long cooldown (it shouldn't be spammable, perhaps 20 seconds?) The skillshot should be pretty wide (a bit narrower than Nami's ult and a bit wider than Lux's shield) and medium long to slow/boost a handful of champions in one shot, but also slow enough for enemies to dodge it with ease if they're quick (perhaps as slow as Anivia's Q). Passive is lost when this ability is on cooldown (as usual) but notice that you'll lose your passive for a longer time due to the long cooldown, so use this ability wisely, especially during a period where you'll have to roam a lot. As the saying goes: "You win some, and you lose some". Your job is make sure your team loses as little as possible,

Graphic Suggestions :) Janna summons a wide "wind-wave" which travels slowly in a straight line. When a champion is hit by the wave, a small whirlwind summons around them while the speed-up / slow-down graphics shows up depending on if it's an ally or an enemy.

Oh, and if this rework becomes true (I doubt so, but IF) please change the ability name to something else, as "Zephyr" won't fit the ability effects. Perhaps "Surging Breeze" or "Gust Wave" would be better.

And as I said, tell me what you think about my suggestions, all the good and bad. Thanks :)