In extension to havok. I played a bit of GW2 back in the day and one thing i really enjoyed was the dye system (i am a sucker for cosmetics) but one thing i found awesome was the fact that mobs had a random chance of dropping an unidentified dye which could turn into anything. but at the same time you could craft hues of dyes with cooking of varying rarities and material costs and buy them at cash shop. so this meant that dyes was
A) dropped at low rates by mobs
B) Able to be crafted
C) Able to be purchased for real money.
i think something along those lines could work? like i know its not a classic mmorpg in the whole “boar can drop a twohand greatsword” but it could still be found in chests, titans, whatever. just found in the world. could be crafted by the crafter profession.
to sort it out you could have “rarities” of wearables (i know its subjective how good something looks but from plain metal pants to flaming lava pants of death) and then have A) be all over the spectrum (common to super rare. obviously rare being harder to get) B) have various “max” rarities (so you can make a common random wearable but you can also make a super rare random wearables for waaay harder to get materials) and then C) would be cashshop purchaseable and have a guaranteed chance of a certain wearable rarity.
The problem with this system and with chests would be that you would need a “Collection” system akin to trove (which has done a dang good job of it) and im not sure if that is what the devs plan or they want them to be physical items.
Those are just my thoughts on it