You should be able to upgrade your parts so that the stats are equivalent to the next set.
The upgrade would increase the stats to the same + of the next set. - mohawk +2 body upgrades to the stats of davey croc +2 body but keeps the same model.
This would widen the variety in part selection especially for those who have reached lv150 and are wearing illuminum/bladium/plasmodium because it is the best part.
If this was introduced, they could wear different parts such as a mohawk head, neg volt body and spike arms - all with lv150 stats.
However they will need to upgrade it to the specific level which means you may have to upgrade alot to get from mohawk to illuminum stats.
The cost should be 10,000 coins.
That's all.