CEO Jonathan Meyer provided the following statement during a recent announcement:
We feel the story of psyscrolr serves itself better updated over time. A more episodic feel invites players to want to come back to the world, continue their save, and find more. An example are the letters strewn throughout certain levels of the game. There are more secrets we plan to add in a further update, as well as hidden mini-games added to the game to enhance replayability with leaderboards and Miiverse features planned.
Source: Nintendo Everything