We need to have a vote if we should sets to the rarity score, below will explain what this means and what impact this will have.
Today each NFT get a RS (rarity score) based on how common the traits are. The proposal suggest that in addition to the RS, Sets will also be added.
To understand how this could impact your current NFTs, use the NFT collection "Lights Out" and toggle between "Rarity Score + Sets" & "Rarity Score" in the dropdown called "Scoring: https://www.rareboard.com/lightsout
Example: This NFT pictured below (#458) will likely get a much better RS if we implement RS + Sets, as it would get a "Redx3".