There is a conspicuous space for up to 3 new guide books and a number of things that could use more explanation in game:
-Some of the game's less obvious mechanics such as optimal ammo type usage
-The general principles of ship loadouts
-Basic tactics and maneuvering
Most of these have already been explained 10+ times between the forum and the steam guides but would be much more useful in a format that could be pointed to in game. There's only so much space and time to explain everything in crew chat after all.