Reading all your point of views here, I'll refair to it generally:
Obviousely if you write a review, you are willing to influence the rating. Its like voting, you want your vote to influence on the final results. With those ranks of about 10,000 for a collabs/PR, and about 0.0001 for the rest, its realy hard to influence on the final rating.
Personally, I dont pay much attention anymore on the ratings: I look for the percents that are given, and then "low" it a little bit, assuming that peaple that rate/review would frequently have a positive opinion about the album, but other opinions could exist also...
I assume that another method to solve the problems of impropriate rating/reviews could be taken, rather than the existing ones. Without the nessecity to read everyone's review, to decide if he/she is a 'decent' member or not.
On the one hand, I could say that these issues, along with reviews representation, are not that important. but on the other hand, such things in general would result in less and less enjoyment for visiting and surfing in this site.