Arrow length effects the spine (stiffness) of the shaft. You can use many different arrow combinations with a given bows weight and DL. I would paper tune and see how your arrow is flying. If you don't want to shorten (stiffen) your arrow and it needs to be stiffer, lighten your point weight. If your arrow needs to be more flexible, increase your point weight. If it paper tunes and flies good, don't mess with it.