Specific to WN, using romance as an example, this genre tend to garner more views easily. A simple exercise to determine this would be to look at the number of views a romance novel tend to garner on its days of features versus a fantasy/system novel. This is specifically to views ONLY. With regards to powerstones, it is a different matter.
With regards to collection, I can only use examples gained purely from hearsay. Before being featured a certain novel was sitting close to 1:1000 ratio. For every 1000 views, it was getting 1 person to put it into their collection. During it's front page feature, it was 1: >3 digits with 43k views. This leads me to conclude it is about the crowd and the front page crowd are far more receptive to putting a new book into their collections (yeah, love that crowd man).
It was featured alongside a novel that ended in the top 80s in the week prior. That novel had a SYSTEM in it's title and a high volume of updates/ views/ reviews by the time it was featured. In the following week , I believe it was closing in on 1m(from 500k or so) views and ended in the top 30s. New originals are not allowed to be featured once it is above 3000 collections currently with the exception of daily updates.
I realize my above examples are reductive in terms of your question. To cover the final angle, I believe that until a novel has proceeded to the front page and spent some time in the back end of WN, gaining an accurate representation of views:collections is not possible.
I believe this is where your reviews create a dissonance and I do not admire your position. Should a novel you review to have a score of lets say 5 and it breaks into the top 100 in the next week, how does said review stand?
With the cooperation of the author, you could weigh out your review with the views:collection ratio I suppose but wouldn't that defeat your purpose of curating by your own established standards/framework?
All the best with your site man!