I think if you have points for above/below sv%, you should have points for goals against as well.

If you wanna make it as complex as the rest of your scoring system, you could do it like this:

Goal Against by player with career point-per-game avg above 0.75 = 2 points. So if a good player scores, 2 pts.
Goal against by player with career ppg avg btwn 0.50-0.74 = 3 points. If a mediocre player scores, 3 pts.
Goal against by player with career ppg avg btwn 0.25-0.49 = 5 points. If a bad player scores, 5 pts.
Goal against by player with career ppg avg btwn 0.00-0.24 = 10 points. If Darrol Powe scores, 10 pts. lol

Only problem is for players with not many games to their name. Maybe if they have less than 100 games, any goal against is worth 4 points lol. That puts them between the 2nd and 3rd level lol.

ALSO: If you have this and another legit league, don't get them mixed up for the week... lol

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16 team roti keeper (yr 5/5, keep 6)
G, A, +/-, PIM, PPG, PPA, SHG, SHA, GWG
W, GAA, SV%, SO
2c, 2lw, 2rw, 4d, 2g, 8bn

C: Stamkos, Backstrom
LW: Sedin, Landeskog, Ott (C), McGinn
RW: Purcell, Brunner, Stewart, Boyes (C), Hornqvist
D: Letang, Byfuglien, Streit, Carlson, Beauchemin, Barrie
G: Ward, Schneider, Ellis