they should make a new series just focusing on the saiyan race. as they begin to dominate the universe and conquer planets. here they can also explore the first ever super saiyan. the saiyans battle a race who are putting up a fight. one warrior ascends among the ranks to save his people and becomes their leader.
maybe they could also battle the namekians but the battle ends in a stalemate
then the series can end when the saiyan race becomes enslaved to Frieza's ancestors. have it ending with the super saiyan taking on the leader but falls in battle.
dont call it dragon ball or anything. give it a new title like "Saiyan" or something