Managed decline sounds like an interesting concept - do you have any specific examples of what that would entail? Would it encompass, say, stories where you start off with a certain amount of soldiers under command (and a black-and-white morality) and have to fight a war, managing both the resources and having your morality stats change? Or maybe playing as a character suffering a neurodegenerative disorder, e.g. Huntington's, and then deciding what to do as your motor skills stats etc. decline? Anyway, it's an exciting idea
A story where you play from different perspectives would probably be difficult to pull off. It cuts off an avenue of suspense and unpredictability in a story, would probably be confusing, and might be a bit like playing chess with oneself, I think, though it's again an interesting concept that could probably be worked into an innovative story by the right creative mind.
This isn't a story structure per se, but I've been thinking for a while that CS games do have the potential to address moral dilemmas that involve attitudes that aren't exactly- well, met with much warmth, especially when it pits logic against emotion. For example (and I apologise if what I say is confronting to anyone), the issue about whether or not life support should be cut off after a certain period of brain death. Some would argue that it's a 'waste of resources' to keep it on, and they would be immediately attacked for being cold and heartless. In a story you could have a scenario where the MC has limited resources and has to make such a choice. Stories probably exist where you have to make difficult decisions, but I'm referring to this in the context of a realist story that is meant to model current ethical issues and be confrontational to a certain degree. In non-interactive fiction such views that are expressed are interpreted by some readers as a reflection upon the author, who is then accused of said coldness and heartlessness. CS stories are designed to be accommodating of different readers, so it would allow any writer wishing to explore such issues a degree of protection.
Sorry for the length of that, and I apologise if it didn't make much sense (was about to go to sleep but this got me excited).