My anecdotal experience is very different than yours. People on alcohol have issues managing their emotions and impulses, and a lot of men get aggressive and violet - and most of the people that I encounter that consume cannabis you'd never know.

Now, that doesn't cover every case, I run in to people who vape cannabis all the time, and they seem to have some emotional effects from that, but if someone is going to abuse a substance, I'd much prefer that was cannabis. Alcohol is a poison, look at the biology at work when your body processes. Re: cannabis, smoking anything is unhealthy, so maybe don't smoke.