Hello Gordon,
Thank you for sharing your thoughts on creativity. I have been working on a large project for CFA Institute members about how to increase creativity and there is much overlap with your short description above, especially with regard to boundaries. So naturally I am in complete agreement with your thoughts and insights.
I will add to your descriptions a form of creativity which is a stepped down intellectualization of intuitive insights. In other words, those ideas coming from just beyond the grasp, of not just the individual, but of culture itself.
With smiles,
Jason