Living in a legal pot state, my primary complaint is that MJ does not face the same marketing limitations that alcohol and tobacco do, which makes it more dangerous to young people. As a drug, I don't view MJ as "higher risk" compared to alcohol or tobacco; but kids/teens/young adults around here view it as a natural, safe, more socially-accepted drug.
I'd like to see MJ taxed like crazy (same with EtOH and tobacco) and outlaw deceptive radio ads, billboards, etc.