I propose the opposite to Pay 2 Win model. Namely: Win 2 Pay.
Win 2 Pay: player must complete story mode / a huge portion of the vanilla content before being able to purchase items shown in the in-game Marketplace / Store.
Imagine this: The player visits the Marketplace and they see a shiny cosmetic item / weapon skin / alternative model that would make their avatar looks rad as phuck. then a prompt tells them that they must first win the game to be able to buy the item with their REAL money.
So the player is over there, thinking: “I have the money right here! But the game doesn’t allow me to buy it unless I win the game?! What kind of fucked up system is this?! Don’t you want MY MONEY?” Well, player. Yes I DO want your money. But I would rather you PLAY MY GAME.