We have blends with up to 10% micro and they still work very well, but it is true that it will decrease cold throw. Try slowly reducing micro % by 0.5 - 1% at a time and see if that helps increase cold throw. whatever you reduce the micro by, I would increase paraffin, soy, palm or a combination of those.
what reason are you adding in PE waxes?
Are these container candles or freestanding votives, pillars, etc?