I Love Soraka, But..
She's one of the most unfun supports to lane against, and it's not even because of her heal, but her Q.
It has one of the shortest cooldowns, with a fairly decent sized AoE, low mana cost, and if it lands it heals her. I'm aware that it has to heal her because she sacrifices some of her own health to use her W, but the way it is now, it's incredibly boring, and frustrating to lane against her. You can't really poke her because the moment you get to close she can hit with Q, and then just heal back whatever damage you dealt, making it a pointless endeavor.
I don't want her nerfed into the ground, I enjoy playing myself every now and then, but just up the mana cost on Q so she can't spam it in lane as frequently.