"If every conviction required a full 12 person jury vote, we would likely find that the threshold for acts treated criminally would steeply increase as the founders intended."

You must be unaware that Oregon does not require a unanimous verdict except in some homicide cases.  Louisiana also permits 10-2 verdicts.  Both have been upheld by the US Supreme Court.  

"In Apodaca v. Oregon (1972), the Supreme Court held that the Sixth Amendment requires unanimity for a verdict — but that the Fourteenth Amendment does not carry this rule over to the states, and that even 9-3 verdicts are constitutionally permissible."