However your projection is a little off. State legalization means little as long as the federal government is interfering with it's war on drugs. Possession of marijuana is also a federal crime. The federal government helps to finance state and local law enforcement and one of the results they expect in return is arrests for drug charges. This ultimately results inb the problem you recognize of people in prison needlessly for non violent drug charges.
Until we can end he war on drugs, abolish the DEA and office of drug enforcement policy, and repeal those federal laws I fear the positive changes in state law like Alaska are meaningless.