If it's injury rate reduction you want, then you really need to implement a multi step process to reduce those factors that promote injury probabilities.
I. Reduce the travel burden - so no more Queensland, Tasmania
II. Apply the rules even handedly, so that some team's players can stop getting whacked in the head while others are protected
III. Set fire to the rules committee... or something, then get rid of the stupid uneccessary rules like nominating for ruck, stop rewarding head ducking, stop rewarding players who 'trip' over opponents who are going for the ball...things like that
IV. Shorten the quarters - cap time on at 5 minutes max
V. Stop playing a Winter game in the Summer months.
.....and yeah, naaah, won't happen