While I find my reasoning for not wanting a promotion to be logical, I can’t shake the feeling that I’m being stupid for not seizing the opportunities that are right in front of my face.
I felt the same way when I worked a corporate job. I accepted promotion after promotion only to find myself in a position very far removed from what I loved about the industry. In short, it was more management and schedules, less creativity and my own ideas. I've since learned it's not a bad thing to come up with your own career trajectory and goals. Try communicating that to your boss (and your boss' boss) with your timeline in mind. These exact opportunities might not be there when you're ready, but something equally great will be.