R&D: Can we use states for game modes?

[freezy]

If you look at pyprocgame's modes, they are stored in an ordered queue that allows each mode to decide whether a switch event bubbles down further the queue, or not.

It would be awesome if our state graphs could somehow be marked with a priority, and that our nodes would have access to that priority, so we can add a similar feature by using a state graph for a "mode".