I'd take on something substantial, but not too weighty. Everyone's going to be talking about things like abortion - but for something "fluffier" like Coke vs. Pepsi, you would be hard pressed to find sources. (For the record... Coke
)
How about
:
Why licensed drivers should be required to retake their written and/or road tests every few years
Why smoking should or should not be banned in restaurants and bars (Big topic in NYC right now)
Why the drinking age should be lowered to 18
Good luck
