I don't really get what's your problem guys.
Okay, you're right: it was easy for Kishi to just revive the dead - but somehow I liked it...
I can also imagine why he didnt kill off Hinata. I think it fits to Pain's character. After all, he wanted to protect his friends too. And he said that he wanted to test the Kyuubi's strenght (though I don't understand why).
yeah, and it seems like he couldn't bring Yahiko back to life b/c it would have killed him.

I agree that it could have been a little more "sophisticated" but
if you don't like the series anymore, maybe you should stop reading/watching it.

So long.