I've been thinking some about what drug policy should look like, from a few angles:
Drug prohibition hasn't gone very well. It's very expensive, leads to a lot of crime and jail time, and dangerous drugs are still widely available. Plus a lot of the ways that we think "drugs are dangerous" are actually "getting addicted to something illegal and inconsistent is dangerous.
Which drugs we prohibit is a historical accident. Alcohol is substantially worse (Nutt 2007) than many illegal options.
I don't like recreational drugs. For a social lubricant I strongly prefer food, music, dancing, singing, or gaming.
Lots of people disagree with me on this.
I'd like to see a policy that approaches drugs from the perspective that our society is going to have some, and pushes people in the direction of drugs and approaches that are least harmful. Something like high taxes on alcohol and cigarettes, while removing restrictions on vaping, cannabis, LSD, MDMA, and psilocybin.
For extremely addictive drugs such as heroin and other opioids, there are probably social environments where they could be consumed safely. Unlike alcohol, they don't lead people to hurt those around them, and mostly cause harm through the efforts people will take to obtain more. You could imagine some sort of "heroin retirement" that mitigates these issues by having you put up funds to pay for heroin and nursing-home style care for the rest of your life.
When considering the effects of various drugs there's also the way they tend to make people change. Stimulants typically increase productivity, cannabis often reduces ambition, LSD can give people a sense of oneness that can make them more altruistic, etc. I'm not sure if policy should consider things like this.
Overall our current policy is so far from reasonable that there are a lot of potential ways to make it better, and I think the recent efforts around marijuana legalization are a step forward.