Last night, I finished adapting Levi Kornelsen's Ouroboros Engine to be a drop in StarCluster resolution mechanic, which I'm calling StarWorm. Ouroboros is based on StarPool, but Levi put GM-mediated Stakes into the system. In every situation where dice are thrown, the GM sets the stakes. There can be several stakes, of two types. I call them "You Might" Stakes and "You Could" Stakes in StarWorm. "You Might" stakes always start off with "You Might", as in "You Might Die", or "You Might be Shamed", or whatever fits the situation. These are dangers, and they will happen unless you buy them off with a success. "You Could" Stakes always start with "You Could", as in "You Could Seduce Him/Her", or "You Could Make a Great Impression", or "You Could Lop Off His Head", and the like. These are opportunities, and they will not happen unless you trigger them with a success.
One of the cool things that happens with this concept is the granularity of action is whatever you want it to be. Want to zoom in on something? Make the Stakes smaller. Want to bite off big chunks of action at a time? Make the Stakes bigger. You control the scope of the action, from task to conflict, by setting appropriate stakes.
Another cool thing you get with this concept is that the GM no longer rolls opposition. By setting the stakes appropriately, you are giving opposition. Stack "You Could Die" on top of "You Could Be Badly Wounded" on top of "You Could Be Lightly Wounded", and there are three levels of opposition which the Player has to either buy off with successes, or suffer as consequences.
A third cool thing is that the dangers always match the situation. You can set up situations where the repercussions of failure are deadly, and others where the consequences are minor, and still others where the consequences are just plain different, and the system can handle it. You can say "You Might Break a Leg" rather than have Constitution (Hit Point) damage. You can say "You Might Be Emotionally Devastated" instead. Whatever makes sense for the situation.
Next I test the rules out in play! If you can't wait, though, get Levi's Ouroboros and check it out!