Indeed, this is one of the things I've been planning on doing one of these days: proper ICM. It's not that hard to do -- what's hard, as KriegerDaemon is finding, is getting it to work consistently and with minimal cpu impact. When we built our claymores for CoC_Mines (which use the same principle that KD is using), the biggest time-consumer wasn't scripting the effect, but making it work reasonably smoothly.
With ICM, the problem is multiplied, since we're talking about far more projectiles, a bigger lethal effect, and salvos of 4 at a time.
Actually, I put my comments in a thread in one of the scripting forums here.