And if the "enough one stars" system doesn't work out (I have no idea how difficult that is to implement), I for one will gladly volunteer to help get rid of the stuff that really is there for no reason.
First and foremost of my criteria would be whether or not it seems that the review is in any way serious. The pure hatefests and "reviews" only meant to mock the official reviewers will be meeting my Review Hammer of Doom (a decendant of the hammer Mjolnir, by the way. Hey, when you're a Norseman, you get certain perks).
As for the rest... Well, basically, the writing should at least be legible. Length is not a criteria in itself, though I have noticed that there is a fairly strong correlation between very short and very bad reviews.
Perhaps such a team could also be able to edit the reviews purely for formatting reasons? You know, turning one loooong paragraph into several shorter ones, that kind of stuff. No changing of the actual content, of course. I know that we can edit our own reviews, but if you're not doing such an easy thing correctly the first time, then I'll wager you don't care enough, and thus will only be annoyed that people ask you to improve your work. So might as well cut down the process with one step that makes it quicker and less painless for everyone involved.