ROH.... nobody said it was perfect it is a quick look.
On the other hand the weaker teams in a region would bog down the stronger and vice versa. For example, a team like Irmo in Region 4 has an opp W% of 63% means that on average all the teams they play are fairly strong. I do not know the girls as well but on the boys side as an example, NW has an "easy" region yet they still play tough opponents and managed a 62% rating.
Again not perfect but quick.
