I see tanky supports becoming strong in S4. This includes the new/buffed Soraka.
I agree with this.
Riot is hashing out the AP ratios so while in preseason someone like Fidd or Annie is going to be really strong, I see them getting nerfed down so they're not an AP mid lite basically. If I had to guess, Riot is going to really gimp their CC durations and have them scale on total AP. So someone like Fiddles or Annie will still bring some dumb damage to lane, but they won't have things like a 3 second point and click fear until late game.
Meanwhile, someone like soraka being able to spam damage/shred or Leona being super tanky is just gonna open up double assassin comps even more.