Why has no one mentioned a magnifying glass? Or a tape outline for a crime scene (where the body is found)
The design is okay, and I know she wants you to use the old board game style, but why not update the look a little?
Using a grunge or splatter brush on the black line in the same mint green color would give some interest, while still keeping the basic design intact - and if you do it right, it'll look sort of like a suggestion of blood spatter (without the blood).... while still keeping the color count low (since this is being designed for print).
Of course, it looks nice as it is, and a clean, simple look is good, too.