If you are worried about underdriven pullies, such as the Unorthodox set, having an undesired effect on your electrical system/stereo system, look into a set of lightened pullies instead. A lightened pulley will produce similar gains to an underdriven one, and won't have any negative side-effects.
Because the crank pulley by far the heaviest pulley out of the set, the maximum bang for the buck would be to replace JUST the crank pulley. Only minimal gains can be had by replacing the alternator/power steering.
So, with that in mind, I'd recommend the MrJosh lightweight crank pulley (about $90, look in the vendor forums at www.rs25.com
), or the Perrin crank pulley ($120, but looks really nice!). I have the MrJosh and couldn't be happier with it.