Subjective perspective - smoking is really bad, can be dramatically improved with good vaping but its still harmful. One of the great side effects of legalization - health-conscious people have less damaging options for consumption. Eliminated by eating the material, but then effects are a bit different. There have been some rumors on lower sperm count/lowered movement, not sure if related more to smoking any material or something in cannabis causing it. For short term buzz maybe some nasal spray would be great (again, legalization can help this get done properly).
Then there are mental effects - people are mentally incapacitated, usually even day after is felt, short term memory negatively impaired. Long term frequent usage leads to mild dependence, which can be given up much easier compared to ie cigarettes. Can trigger dormant mental illnesses, and amplify them with long term usage (I guess paranoia is the most common one, schizophrenics would be also bad - same can be achieved with any other drug including alcohol, or big shock like car crash).
Side effects of behavior can be quite destructive too - 'munchies' cravings for unhealthy food (sweet, fried etc) - long term disastrous for health just like any other overeating.
I can't think of anything else right now, but for sure there is something else. Overall relatively low harm, especially when things like alcohol and tobacco roam civilization almost freely