> Over time, cannabis has also allowed me to analyse and think on the past

There is danger in attributing something broad like this directly to drug use. Can you only reflect while high?

It may be that the initial psychedelic sessions helped break through some mental/emotional patterns you were suffering from (positive impact), but that continued regular use has an overall negative impact on mental health. That's been my experience with psychedelics and how I've seen them work on those around me, at least.