How is Krillin a better character?
Krillin can beat the crap out of supes if you think about it.
1. He knows martial arts
2. He has a bigger attack
3. He can destroy a world since frieza did it with a powerlevel of 5,000
4. He has a faster fighting style
5. He's fought with Goku
6. He's no slouch
7. He can figure out ways to bring the best of opponents down
8. He could cut through mountains with his disc.
Plus Krillin is a normal human, as opposed to Superman having powers. Krillin can do things like shoot discs, but he always gets his ass handed to him.
By opponents that can destroy galaxies and such, but krillin is stronger than 500 atomic bombs.