So, you want to play support and have an impact on the game?
Well, may I introduce you to 
Blitz is a load of fun to play, does a good amount of damage even when built tanky come late game, and during laning phase that pull of yours is probably the most game changing thing you have. I've been complimented by almost every ADC I've supported when I play Blitz, and with good reason.
With most supports the effects are much more passive, like Soraka for instance, its hard to tell how much that soraka is doing to help you when all she does is heal and occasionally silence the enemy. With Blitz, well its obvious what he is doing, he's pulling the enemy in, and then knocking them up, giving the ADC a chance to kill them.
So, if you are getting autofilled support, just remember,
"The time of man has come to an end"
"Oh hey blitz, I see you're aiming for our ADC. It'd be a real shame if you accidentally grabbed me huh?"
Nah, nah, I dare you to grab me. I have my Ionian boots ready for just such an occasion.
I generally cook cow head in a robot helmet. Works really well.