One feature that RKSL has that I don't believe your countermeasure system does is that flares act as decoys even if they were launched before the missile. They also act as decoys on the "Magic Radar".
From tests and having a glance at your code it appears that missiles are only affected by flares launched by their target, and only if they are launched after the missile is.
Mando Missile ArmA for ArmA 2
in ARMA 2 & OA - ADDONS & MODS: COMPLETE
Posted
One feature that RKSL has that I don't believe your countermeasure system does is that flares act as decoys even if they were launched before the missile. They also act as decoys on the "Magic Radar".
From tests and having a glance at your code it appears that missiles are only affected by flares launched by their target, and only if they are launched after the missile is.