I think it should only be used in a private place or with friends at a private place.
Gong out in public while high or smoking in public both should be illegal, just like how public intoxication is acted upon in some states, or how smoking a cig near a public establishment is not allowed (unless allowed ofc, like a smoking patio or a bar)
I dont give a stuff if you smoke it at home. its your choice and you are in a safe place.
Also, the only addictive thing about pot is the effects of it. I think it should stay at the age of 21 like in colorado. Like alcohol, it does inhibit decisions and can be dangerous to others in certain situations.