Drug legalization directly leads to less drug abuse. The evidence is very clear on that point. However, you don't do it like San Francisco or Seattle. You model the laws after Portugal.

I'm not saying get rid of professional licensing. I wish to divorce it from the control of the state.

Example 1:

No one needs to be licensed to cut hair or do nails. Really. Come on.

Example 2: a doctor would still need to be licensed to carry liability insurance, but, if a person trusted an unlicensed doctor to do doctorly things then that's on that person. This would also eliminate much of the onus of whistle blowing or having an opinion that contradicts the state's position on certain topics. The threat of the state pulling your license would be gone. Sure, you'd still have to deal with an employer like a hospital, but, if you were in a private practice, you could tell anyone to bugger off if they don't like your opinion on sugar or vaccines.