Seeing sqrt(x) is the same as pow(x, 1/2) (i.e. the inverse of pow(x,2)), you can try tweaking that hard-coded 2 with different values, e.g. what you've got now is the same as this, so replace 2.0f with a variable and see what happens:
Any tips on how it can be tweaked?
int sum=0; for( int i=0; i!=count; ++i ) sum += pow( scores[i], 2.0f ); score = pow( sum, 1/2.0f );I guess larger numbers give more weight to perfectionists, and smaller numbers are closer to a regular average.