Not a priority, but something to add in the future maybe. The only potential problem I see is that the writers would have to spend a ton of time coming up with background lore for the codex--FFXII and Dragon Age have about the ideal codices in my book and they look like they took ages to write. This time would almost always be better spent writing content for things in the actual game, like quests, characters or dialogue. Maybe if the game takes off SE can commission a few freelancers to research and write up a codex while their main guys continue to work on more relevant content.