Yes, I'm quite clear that your stance is the legalization of marijuana for only certain individuals and abuse is still subject to legal action.
However, my stance is quite clearly that I don't see any reason to legalize another substance that can lead people to ruin their lives.
It is my theory (I have no research to support it) that the majority of people being arrested for weed today would still be arrested if it were regulated. Many are underage, and many people profit from selling it. If weed were regulated, the underage and dealers would still be subject to prosecution. I strongly feel that the same people who would be arrested for weed-related crimes would not really change, and the set of people arrested would be identical.
Given this, what is the rationale for legalizing it? I've often seen the analogy that it is similar for a man of legal age and responsible demeanor to have some Gin and Tonic, but if this is true why do we need weed? There is already a perfectly legal alternative available but for some reason it is not adequate.
Basically my idea is that if changing the legality of an activity will have no effect on the number of arrests you make, there is no reason to alter its legality. This is why while I'd love to see alcohol and tobacco restricted, it wouldn't work. They are already legal, and making them illegal would have the same people arrested for different reasons, so why bother changing their legal status?
I guess what I find hilarious about it all is that half of the hardcore legalize weed crowd I run into is younger than 18 years old, and if it were legalized they would still be underage and still get people arrested for selling it to them. If you are an underage user when it is illegal, would you stop when it becomes legal and wait until you reach the right age? I think not.