Need to be illegal? probably not, and the only good reason for legalizing it is because of the ridiculous crime charges it causes, both in amount and intensity. The only reason I'd want it legalized is because some people make stupid fucking shit decisions based on weed. The drug may not be addictive, but the habit is.
I know a druggie couple with five kids: oldest to youngest- one's a psychologically neglected pothead with a flat personality; the next is an emotionally neglected wierdo; then a little girl with a speech impediment, since her parents don't care to help fix it other than "talk right"; a trouble maker with a heart disability that gives his parents checks; and a baby that's already got breathing problems because they smoke around it all the time. I've no kindness for stoners, because the rule of "The few, stupidest members are the loudest" fits plenty of times, but it's certainly the majority for this case; and my patience towards those levels of awful is awfully low.