Ron's mother kicks ass in the final book. Your argument is invalid.

…But even if it weren't, the fact that Evangelion chose to go with more realistic is to set it apart from other mecha shows. There's no way that this show would have had the impact that it did if Shinji had just been your generic hot-blooded catchphrase-spewing hero (which, incidentally, is why I found myself disappointed with the plot of Tengen Toppa Gurren Lagann, though I liked the animation). Think about how generic Spider-Man would be as a superhero if he didn't start out as a teenager, and he didn't have to go through the various internal problems and bad publicity – it's what set him apart from the mold to begin with.

Also, I'm pretty sure that Shinji kicks ass many times. In the episode that the screencap is from, he shrugged off having his biomech's arm cut off and continued to pummel his opponent with one hand.