The director's cut does add some interesting new and extended scenes, there's some great new Sean Bean stuff, but it doesn't change the overall tone (and your issues with the movie).

You're absolutely right in that it seems they chose the path of least resistance, it lacks punch I guess. But then... Clash of the Titans, its sequel and Immortals all seem to have gone too far in the other direction. That's not to say it's all bad though, there are a few elements I like. I think they chose poorly with their casting of Achilles. Brad Pitt might physically be apt for the role, but to my eyes he was always too 'modern'.

I like both, but I can't really be trusted with these sorts of vaguely hard sci-fi movies.

Just watched This Film is Not Yet Rated because it was mentioned in a couple of the commentaries.  Interesting documentary that was pretty much what I expected it to be.  If you're told the premise of the documentary you've pretty much seen it with a few exceptions.  Some of the side by side comparisons were interesting but when you look at who's in charge of the MPAA none of the rulings they came out with were surprising at all. 

The lone quote that made me rethink how we should look at movies was actually a statement by Kevin Smith.  The realistic violence that shows how horrible it is to get shot or blown up should be the PG13 and any movie with bullets flying around and nobody getting hurt should be the R.  The premise that guns aren't dangerous that movies portray is probably adding some to the problem of rampant firearms in our society.  Not the number one factor by any means but a possibility. 

Hopefully with the swaying of public opinion in regard to gay marriage, the NC17 ratings given to movies with homosexual content will tend to work themselves out moving forward because unfortunately I don't see the MPAA being replaced by a better entity any time soon.