It may sound strange, but usually the simplest is the best, although it is often the hardest to carry off.
It’s the same with painting, I feel, where knowing where and when to stop is the hardest thing, the chance brush stroke that looks so good… you’ve just got to leave it and move on and hope you can create a few more.
Sometimes pressure can help. You give yourself a limited time and this quite often works, making the brush strokes freer or more aggressive (yes, aggressive!).
So, in fact, I don’t feel you can plan too much. Each creation is just that, a creation, and can take on a life of its own. Maybe that’s why I like it.