I truly underestimated the importance of forward lean. I find that if I am in the park, I ride with as little lean as possible. This allow more flexibility while riding on rail/boxes (flat base). If I am riding trees/mountain, put as much lean as comfortable. This make me more confident ripping blue and black diamond runs.
Note: If you find yourself busting you bottom on heel edge, increase the lean. Not knowing this information made be buy another snowboard, which I did not need. Hope this helps.