The only concern I have while snowboarding and skateboarding is to have fun. There is enough pressure with school/work, etc, I do not need that while boarding. For me it seems that having fun makes for natural progression.
Setting goals does not work very well for me because it feels like a chore.
I started going on steeper runs when the greens or blues started to get somewhat boring, meaning my mind/body were ready for steeper terrain.
I wanted to have more fun and more fun was to be had at steeper terrain.
I do not know the technical terms (dynamic, etc), I just started going on steeper terrain until I felt comfortable riding it. Since I knew I was going to be somewhat slow on steeper terrain at the beginning, I kept to either the left or right of the run, usually the one with more snow, that way I was not inconveniencing the faster riders going in the middle. Also since I was not in the middle I could stop on the side of the run away from all the traffic if a felt like I could not handle anymore turns.
Stickz: Skateboarding is so much in the summer. You can always look forward to skate/snowboard with your kids. I see tons of dads skating with their kids at my local park.