lowering the front is one thing, lowering AND stiffening front w/o corresponding changes at the back may make the rear end more prone to snap oversteer and weird transitional handling at the limit of grip. subies are set up at the factory with the front a bit stiffer than the rear, but increasing that difference is not necessarily a good thing.
I just don't get what's so bad about that "dreaded wheel gap." Suby engineers did not put it into the cars to piss off owners, it's there to retain sufficient wheel travel at the front so a suby drives like a subie on rough roads (and not like a slammed hondEr). as nose-heavy as subies are, you NEED more wheel travel at the front to keep from bottoming out all the time.
if you friend is more worried about how the car looks as opposed to how it drives, go ahead and tinker all he wants.