Don't mess with the coil strength... I had both these problems and they are pretty easily fixed.
A great fix for the POTD problems is this:
http://www.pinbits.com/index.php?main_page=product_info&cPath=13_48&products_id=491
A fix for the shooter lane skill shot lights is putting a thin foam adhesive to where the ball shoots out (I think I got some from Marcos a long time back ...so don't have that specific link)...on mine its enough not to let the ball activate the switch when coming out.
I don't like the idea of weakening all the coils..bleh.