If you're looking for a Founding Father who really doesn't fit the mold, you should become more familiar with Luther Martin. The Maryland Constitutional Convention delegate wasn't really well-known, even among his peers at the convention. He was also drinking brandy, apparently, throughout the event -- a vice that followed him throughout life [source: Reynolds].
But he was passionate and didn't hesitate to express strong views. From a small state himself, the lawyer found the idea of the Virginia Plan (where both houses would have proportional representation based on state population) totally anathema. For three hours, Martin railed against the plan during the convention, and eventually walked out altogether when he thought that the Constitution was going to allow for much stronger central (rather than state) government.
He went on to become Maryland state attorney general for a combined total of more than 30 years. Another legal highlight: He was also part of a team who successfully defended Aaron Burr against treason charges. But he kept up his drinking, and ended up dying destitute in 1826. He was buried in an unmarked grave in New York City [source: National Archives].