Cosmetic items are nice things to collect because while they do not strictly affect your numerical performance in the game, they do offer significant improvements in terms of sentimental value. From emotes to cosmetic gear to musical tracks to minions to mounts, getting your character to look and feel just right can be a singular pleasure. The only problem is when you wind up wanting a particular sort of cosmetic that isn’t available in the game. Not just “I want X as a mount, but it’s not available.” We’re talking “I want X as a mount, but this is a game without mounts.”
Today, we are not curious about what you do collect that your game of choice offers; we’re asking about what you’d like to collect that isn’t on offer. Maybe you want non-combat pets in a game without them. Maybe you want music or housing decoration that is stymied by the game lacking housing. Different looks for your skills? Body tattoos? Colored balloons? What sort of cosmetic thing would you like to collect in your main MMO?