Part of the reason we do it this way is a few years ago I got complaints about defenses ending up with negative scores, and if you had a bad matchup and didn't feel there was a better defense in waivers, you would have the incentive to not start a defense. A good chunk of the defense points in my league is based on net yardage and points allowed (especially offensive points allowed). I adjusted the scale for each up slightly, added a few more things that aren't used often but available in the scoring setup on MFL, and it took care of the problem. You still get negative scores from time to time