I think the best approach is to allow each neighborhood to decide what recreational drugs, if any, can be consumed in public. And only enforce such restriction

I think the best approach is to allow each neighborhood to decide what recreational drugs, if any, can be consumed in public. And only enforce such restrictions with fines, not jail time. Regulating at the neighborhood level makes it easier to live in or travel to the kind of neighborhood you want to be in. People that want to use drugs in public where they live can pick their neighborhood accordingly. The more permissive neighborhoods can tax drug use to pay for any negative consequences of drug use. Maybe they need more enforcement of traffic laws, for example. If we allow everything everywhere, eventually there will be pressure to control everything again. Better to allow people who want drug-free neighborhoods to have them, while ensuring that those who want to use drugs are still able to.