I take it the  " competition" you refer to will be the struggle between the unstructured market, and the soon to arrive, "government sanctioned" suppliers and whatever distribution they bless.
The liquor analogy is interesting . Lets look at beer . Once tightly controlled after prohibition by 4-5 families .  Currently that market is fracturing , into a myriad of small craft breweries. Isnt that where the "pot industry" is now?? What are the overwhelming factors for consolidation in the Pot Growing industry? Quality ?  Price ? 
I trust governments ability to get it more wrong than right.
But I may be wrong.
Nevertheless , I believe the best aspect is that an 19 year old young adult will no longer get a criminal record, for doing something most of the country has tried.