Teemo Suggestion
Teemo's backstory pits him as a scout, and he's got a great kit for it. However, his playstyle is nothing like this, and it really hurts to have teemo on your team most of the time.
My suggestion is this:
Lower Teemo's shroom damage, but make the damage scale up over time, causing him to choose carefully where to put his mushrooms, to be used more tactfully.