good change, but the rarity names are a little clunky, i'd suggest changing them slightly to give them their own unique identities rather than being pre-fixes of existing rarities
Exremely common > Abundant
Very uncommon > Infrequent
Extremely uncommon > Unusual
Extremely rare > Scarce
it's not exactly the most pressing issue, but i feel like some of these (especially extremely uncommon) just feel so long and clunky compared to the others, though this would separate them slightly from their previous/next tiers of rarities, the abbreviations would be A, I, UN, and S, rather than having to use a 3 letter abbreviation in "VUC", making them more distinct overall