If you care fairness, I have 1 extra suggestion that you might be interested in.

It was proven by several data-science research that when users have to votes (or give ratings) and if they are able to see the previous result, then the first few votes have an extremely important effect.

For instance here is one stury, very well written article by a famous teacher Robert West, "of sheep and beer" https://dlab.epfl.ch/2017-08-30-of-sheep-and-beer/ which describes this effect on beer-rating sites.

One way to overcome this effect is to hide the votes until enough votes were collected (eg more than 50). Another way is to hide votes until you have voted yourself.

You can see a form of this effect on HN itself, in particular in Show HN topics.

First few comments basically set the tone of the discussion and its dynamic. If they are shallow, negative or dismissive, the discussion gets stuck and takes a while to recover even if the submission has a lot of actual merit.

This is not a study but a reality for me. At one point on HN I wanted to farm for karma points. That period lasted for a few weeks, I wasn't too intense about it, just a fun question I had.

My tactic? Find something that has something like 15 upvotes and you suspect to be rising quick in upvotes. Create the first comment and your best to make an as thoughtful comment as possible, even if you don't know anything about the topic.

Result: I was always within the top 3 getting between 10 to 50 upvotes.

One idea I have (just brainstorming) force users to make a vote first of 10 random products and only after they see the results.

It could probably use some UX tweaking since forcing someone to vote isn't quite nice, but at least it takes care of this effect that was described.

Thank you for the suggestion. I have implemented something like this but still experimenting with different factors.