We need an idea that's sufficiently detailed enough to give structure, but general enough so that one may still be excessively creative.
An example might be a three-mission strike on a Shivan supply-depot without real details on how it's done, what resources are used, etc. So, theoretically, you could bring in GTVA-man striking against a depot guarded by Count Shiva, that's the kind of creativity this thing should be aiming for.
But at the same time, we don't want to stifle the chance to go completely off-the-wall, like using an intricate ballet of ships entering and exiting subspace to create a big smilie-face to scare away the Shivans... or something.
Just throwing ideas out there.