As it stands right now Skirmish-mode is by far the least interesting. It is simply a mindless Team DeathMatch where you pound your enemies into submission. Oh, and there's power-ups, exciting!

So, one thing I've wondered basically since this mode was introduced is this; since you gain points by killing, shouldn't you lose points if an enemy is revived?
This would force a different kind of playstyle on the mode. One where it may be worth staying back and guarding a corpse, one where getting the execution is high reward and where leaving bodies mindlessly to fight somewhere else can be the big turn-around.

Obviously, the matches would be longer, but as it stands now a match doesn't even take 10 minutes, so I think we can afford it.
Alternatively the refund would not be 100% of the score, but rather a set amount of (for example) the 5 points you gain from a vanilla kill, yet any bonus that the killer received from fighting outnumbered or anything is permanently theirs.