I feel you man.
Thing is, everytime a global threat approaches DC Earth, Supes is usually the last line of defense as Goku is, DC just happens to have more storylines in-between their escalating global threat villains to make it seem more gradual.
Like I said, it's all perspective. You definitely have a right to your opinion and I respect that.
As for Krillin, his kamehameha wave is not as powerful as a young master Roshi or Piccolo's super cannon. He could probably level a mountain, but he's no planet buster. His strongest attack was always his "destructo disc" attack, that's what he was most proficient with.