I would love to invest in the business of growing and reselling cannabis now, first of all it is a noble business that helps people feel better about themselves, and secondly it is quite profitable! 
It's definitely a profitable business. And the more countries legalising it will make it much easier to expand. Also if its legally possible to grow it in larger scales than the quality should improve. A high quality online distribution could make a lot of profit. Unfortunately in my country its still banned.