Running some tests myself there is about a 20-30% difference in damage on kakashi clones

This makes Gaara significantly better than Kazakage Gaara in terms of damage which is to be expected with about 120 less ninjutsu and attack growth.

The problem is the amount all in all Gaara doing about 25~% is quite significant and and would outright beat Kazekage version. The only thing holding Gaara back is the immoblie on chase.

The growth difference is only 150~ about but stat wise its not 15% difference which is what we are seeing in damage outcomes