I have done some small-scale dabbling here and there. Mostly with daydreams.

[Luna is pretty much correct, although add to that a significant amount of simply not being able to bring herself to take on a role not physically necessary to the survival of Equestria, when it would serve as another painful reminder of her sister's absence.]

I don't pretend for a second I will have a tenth of your skill, but if you continue at this pace, you won't have a tenth of your skill.