Interesting topic! I think that could be a bit of a problem with D/s, the Dominant is usually the one who is relied on to be creative and find new ways to punish the submissive. A submissive could be creative, and suggest some new ways of doing things, purchase a new toy, etc. Of course, then it's up to the Dominant to twist her plan so she's always on her toes... sometimes literally
Not having had any experience, I can't say for sure, but I don't think I'd have any problem with a submissive being creative in her submission.
LD