AoE counter-play?

I've just noticed that several champs with standard abilities have pretty high damage AoE pokes that offer no counter-play. Nasus and Morganna just to name a couple. I'd like to see some other champs with similar standard ability AoE pokes have their damage altered to allow reasonable counter-play options. As it stands now, the damage from Nasus is a sizeable chunk up front, then additional damage if you stay in it. Maybe, just remove some of the front loaded damage and spread it into the duration of the ability?