I think if they extend the story, they need to introduce more full blooded Saiyans. Maybe Goku or Vegeta are contacted by a few Saiyan scouts. They are not hostile vs Goku or Vegeta, because they have heard of the Legendary Saiyan warriors who defeated the colossal tyrants in Frieza, King Cold, Cell and Majin Buu. Would be cool imo. Obviously, a lot of kinks would have to be worked out for something like this to happen.
ETA: Where the frick is Krillin in this picture? Is he dead? That's probably why they summoned Shenron Image: http://www.kanzenshuu.com/wp-content/uploads/2013/03/akiba_souken_screen_06.jpg
This post was edited on 3/8 at 3:35 pm