You know the easiest way to do this? Ban out of state mo ey and lobbying in these issues. Make them money come from grass roots, in state donors. The only reason crap gets on the ballot is because of huge outside influences of money. If 51% of people in my state support a change that was driven 100% inside the state, then I can accept it. But raising the threshold to just try to out smart the big spending from outside. Fix the source of the issue and keep each states values as they want them to be.