> There's a ton of unresolved questions: what are the rules around driving high? Who can buy cannabis legally? Which jobs are allowed to be worked high? Which businesses can sell cannabis? What license do you need? What are the penalties for flouting age restrictions on sales? Can you smoke cannabis in a bar? Can you vape cannabis in a restaurant? How is cannabis taxed, and at what rate?

Those are mostly pretty easy questions.

For driving and working high, it's just the same as working or driving in any other impaired state. It's slightly trickier than alcohol because it isn't as easy to measure the level of impairment, but that's also true of many prescription and probably even some over-the-counter drugs, so it's not a new problem.

For all of the other questions, you could just copy the rules for tobacco verbatim and end up with a workable set of rules.