We're developing a game in which friends have several pieces of data that are required in order to fully populate the friends list (name, avatar configuration, etc.) However, it appears that GetFriendsList cannot return arbitrary pieces of UserData.
We thought about using statistics for this purpose (since they can be fetched by passing the ShowStatistics constraint to GetFriendsList), but it appears that we would only be able to get 32-bit integers this way. What's the best way to fetch multiple pieces of data per friend whilst populating the friends list? Looking through the documentation, the best option I see is to call GetUserData repeatedly, but this hardly seems ideal.
(Side note: we're already using TitleDisplayName to store a 6-digit friend code so that users can easily find each other via GetAccountInfoRequest.)