I'm sure I'm not the first person to suggest to gree to stop the sweeping changes, but that's what needs to be done.
If lvl 250s are scoring less because there are no higher lvls. Increase the amount they score.
Don't change the scoring for everyone.
If you change the algorithm to reduce the variance in the scoring. Test it to make sure it works
Whatever change you have made has not reduced the variance.
What it has done is to reduce the scoring across the board.
So lvl 250s have not seen any improvement. And everyone else has less points.
Maybe it's just me, but if you change something. Test it.
Finally, and this is just a suggestion. But try working on making changes that people want. The last few you have implemented have not solved a need that anyone wanted.