Unbrewable potions

Adding a way to access different effects through potions that otherwise can’t be brewed would be really cool. I think it would be awesome for rare structures to rarely have a potion of Levitation, Luck, Haste, and Glowing. Being able to obtain these rarely through Witch Huts and End cities for levitation, Buried Treasures for luck, Witch Huts and trial chambers for Haste, and Witch huts for glowing. These would be incredible, and them being rare one time use, unbrewable items, would make them special, but also make these effects more accessible. (Side note, potions should be able to be in cauldrons, and be found in witch huts, on Java, like in bedrock editions)