Uh, this is a move in the right direction, but I would not call the current situation fine.
Score of posts affected by the now previous system definitely needs to be recalculated. It seriously screws the order:score sorting in almost all cases.
If it's too intensive to do it on the server running Danbooru, then can't it be done offline and then transferred to the live database? I remember something like this being done before.
Or perhaps it can be done in small batches, with them being spread in time.
Here are some thoughts about recalculation and issues associated with it.
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The "favorites = votes" change was implemented at the very beginning of 2016-02-23 as I can see at Github. But checking daily score (aka "Popular") rankings shows that its effect is notable starting from 2016-02-21, which is understandable since people also actively favorited popular posts uploaded shortly before that.
Score of posts uploaded from 2016-02-23 to 2016-03-14 needs to be decreased by the number of favorites they have from Member level users.
There is one issue here though. Posts that got favorites transfered to them due to the deletion of pixiv_manga_sample/pixiv_thumbnail child posts did not get score from those favorites. We can exclude them from recalculation, use different formula for them, or treat them as acceptable casualties.
Score of posts uploaded during Feb 21-22 would also benefit from recalculation, but I'm not sure what approach would be best in this case. Perhaps only do it for the top 50 posts of each day and only decrease score by 1/3 of their favorites from Member level users.
What's interesting, while doing research for the above section I have noticed that score of some posts uploaded shortly after the "any favorites = votes" change seems to be recalculated already. It appears that albert tried to recalculate the scores but stopped halfway.
As for supervoters, as many people have explained before, the idea itself is not something beneficial. Keeping it for admins is fine since they alone won't affect the overall picture too much, but giving such voting power to random people is counterproductive at least.
If the desired effect is to move score away from favcout, then you really should consider previously made suggestion to separate them completely.