Given the condition, it's hardly possible for one to answer otherwise. I would need to add that I feel the question should have been: is the legalization of recreative use of marijuana mandatory for the continuation of the myth of legal consistency... Yes again.
But prohibition of alcohol is, I'm afraid, not in the cards for our world of alcoholics.
Alcohol is not the basis of all problems and banning it will not make it unavailable for the people who want to use it. A ban will make it more attractive and much more profitable for those uncaring of a ban. Unless the ban would be used to force politicians to remain sober while making important decisions or policy an alcohol ban would just create more opportunity for crime.
I don't agree that banning alcohol is good for legal consistency. There are far more other legalities and ethics that go into play for legal consistency than alcohol. Banning alcohol may contribute to legal consistency but I don't feel it would make a considerable dent in any one area's consistency statistics.