If marijuana were legalized bad flavors of the drug would be less likely to exist given there would be little incentive for illegal R&D because the drug would be cheaply available in a legal business of some sort.
/puts on flame resistant suit
I don't believe that and I'll tell you why - because there are many different ways to cross the strains of marijuana plant.
In the Medical Marijuana clinics in California they market various types of strains. Each strain would have a different effect on you. Since I have never used marijuana for medical purposes I can't say if all types work well for a particular ailment, but the side effects will certainly be different. One will make you hyper, one mellow, one paranoid, one sensations of cold, one hot, etc.
The different strains are marketed with names like blueberry, train wreck, snow plow, etc. The medical users seek out the strains that help their ailment while giving them the least bad side effect. Sometimes one strain is available, sometimes not. So the point is, if it were legalized, each person would seek the particular strain that they enjoyed the most (without medical considerations). There would be myriad varieties, like wines.