The way I see it is there is one MAJOR problem being dealt with here: People are viewing the rating system as a popularity contest instead of an actual critique or view on what people think of their addon. Since there is no real way to tell who is voting just to put numbers on a particular addon (what with the anonymity of the internet and all) you can't really stop this behavior short of removing the rating system all together.
The only thing that will be accomplished by making the rating system more complicated or more in depth is to ensure that only 2 groups of people will vote: the very few that actually care and take time to rate things fairly, and the many that the authors get to vote for them to improve their rating.
As long as people on the site continue to act this way...there is no solution.
There are alternatives, but no real solution to the problem.
You could make it a requirement to be a member of the site before users are allowed to rate addons...this way you can keep track of what addons each user downloads....this list could be reset or each addon on the list could be reset every time that addon is updated
example: I download Trinity2.0. Trinity2.0 is then added to my list of addons I have downloaded. When and update for Trinity2.0 comes out, it is moved from my downloaded list to a OutOfDateAddon list. This lets you know that I downloaded it once, but have not gotten the update. If I then return to download the update, it will be required that I provide a rating of the addon. If I do not return for the update, then no rating is provided/required/allowed.
This way only return users are allowed to vote on addons, making sure that the rating is given by a user that has used the addon and has come back and clearly likes it. Also, if the user does not return for the update, then it can be determined that the user didn't like the addon enough to keep using it.
Also, if it is a requirement to rate the addon in order to download the update (for registered users, since it wouldn't be fare or practical to think that everyone that downloads from WOWI is registered) we could make the ratings A LITTLE BIT more in depth. Possibly giving a 1-5 or 1-10 rating in several (but not too many) categories like: Author feedback, Timeliness of Updates, Ease of Use, Computer CPU/Memory Hogging, etc...
This would require a revamp of the rating and the whole downloading system and would require a cache of a list of addons that every registered user has downloaded (possibly being wiped or reset, or removed from the list after a period of time), but is the best solution/alternative to the current rating system that i can think of.
And now MidgetMage55 is not the only non-author to take an interest in this
I look at ratings, but it's not the only think I look at when deciding what addon to try out.