Janna - I stayed away from playing Janna for a long time. Probably because it seems like she doesn't do anything (far from the truth) and Howling Gale seemed like an awkward ability to use appropriately.

Tailwind speeds up allies coming toward her. More speed is always a good thing as it lets you get places faster and makes it easier to dodge skillshots.

Howling Gale there isn't much quite a satisfying as stymieing a Leona or Lee Sin that is trying to gap close onto your carry with a timely or well placed Howling Gale. Nope.

You can either instant cast this thing by simply taping the ability again or you can let it charge up so that it does more damage and the knock-up duration increase. If I were going to nerf Janna I would simply add a delay on her ability to reactivate it. The option to instantly send it off is that potent.

Zephyr - makes you personally faster, which helps with chasing, retreating, and dodging skill shots. The damage on it isn't super high, but it is nothing to sneeze at a and with enough AP it applies up to an 80% slow.

Eye Of The Storm is quite useful for shielding your carry, yourself, or even turrets. You can prevent your carry from taking damage and it also enhances their damage, both of which can really make trading in lane go in your sides favor.

Monsoon is another tool that you have for disengaging and the heal it provides is nothing to sneeze at either. Aside from disengaging it can be used to peel or even push or trap people to but them in a disadvantaged situation.

Her kit makes her really good at protecting her carry even from multiple threats and she offers a similar level of protection to her team when team fights start breaking out.

The fact that she racks up quite the number of assists by indirectly assisting her team mates makes Mejai's Soulstealer a viable pick up on her and when fully stacked it can suffice as the only AP item that she purchases, which makes her overall build very cheap (something in the neighborhood of 15000 gold).

From steering clear of her for quite some time, Janna has stormed into my heart as one of my favorite supports. And for only $2.99 a minute she will blow you away too.