Massachusetts already has decriminalized marijuana, and also medical marijuana, so the stakes aren't quite as high as in other states as I understand it. If I end up voting for it (which I probably will) it will just be to get people to stop talking about it, and because I generally prefer to err on the side of legalizing things where possible. I'd be happy to hear people trying to convince me either way, though.
I'm more strongly in favor of Question 3, since there is some evidence of public health issues related to those sorts of farming.