The problem with letting God call the shots is that practically that means his representatives on Earth are calling the shots.
And whilst some of those people are lovely, some formed the Islamic Republic of Iran.
Still, if we allow for God's rules here...what is his opinion on tobacco, marijuana and alcohol?
The key there Lewis, what are God's laws and what are men's laws, needs to be re-determined, we made a bit of a mess our of that in the past. But we can do much better in the future by learning from the past.
So any recreational drug use and alcohol consumption will be unlawful, medical prescription will be lawful. Most likely this will be mostly controlled by education, as how the laws will be applied need to be revisited.
Tobacco use is highly condemned, but will not been made unlawful. When one reads something like the 'Tablet of Chasity and Purity', then one would ask themselves why they partake of it.
‘Abdu’l-Bahá, Tablet of Chastity and Purity (Lawh-i-Tanzíyyih va Taqdís)
Regards Tony