Great! I think we are on common ground. I am not opposed to any suggestion that can potentially make this war more effective (and, speaking of costs, efficient, too). At the level of details, I do not have sufficiently well-formed opinions because I have not studied the issue --- as that of policy-making -- thoroughly.
No, I do not view changes as surrender.
I have seen enough to believe that, in terms of combating the problem of drug abuse in general, the resources we are expending trying to enforce a prohibition on marijuana would be better spent elsewhere.