From the perspective of someone who sees every review posted on J2O, saying that Cooba removes an absurd number of reviews is itself absurd. There is in most cases a very clear distinction between a review that is well-written and a review that is banged out in ten, fifteen seconds, and it is the latter type that Cooba generally derates, as according to J2O policy. Thankfully, most reviews these days seem to be of the former type, though I'm sure there are a number that Cooba could derate if he chose to be a little more strict but does not.
So, to my mind, the actual actions of removing ratings is not an issue, and is administered fairly. However, what I do consider an issue is that these actions, especially as it is usually the same few users receiving them, often due to their youth or unfamiliarity with English, may scare people off from posting reviews at all, given the necessary briskness of a rating removal notification. To this end, it might be wise to make an effort to personally contact anyone who has had a rating (or more than one) removed, and talk to them one-on-one so that they understand the rating removal was othing personal, should not be taken as such, and to make sure they understand what is expected in further reviews, and that J2O sincerely wants them to continue using the site and expressing their opinions.