And I LIKED the notion of her getting shot in the chest, because first off, It establishes that a few stray bullets aren't going to kill her, just annoy her. I always hated the fact that she can go toe to toe with Superman but a bullet would kill her. It should just annoy her at most. As for making up his own original villain, let's be honest...Diana does NOT have the world's best villains. She has a handful of good ones, but none that simply NEED to be in a movie. I do know his villains were going to be tied into Greek Mythology, so to me that is being true to the comics. Certainly more than the old tv show or the rejected pilot last year, where all the Greek Myth stuff was missing.
And lastly, Whedon DID complete two drafts of the script over a period of two years, and has said so much in interviews (it was one of these scripts that Bruce Timm wanted to use for the Wonder Woman animated movie, till Warners said no) When Warners rejected both scripts, they said come back to him with a whole new outline instead of another draft. But there are two Wonder Woman scripts out there. It isn't like he did nothing for two years.