NomNom is the most complete savegame editor for NMS but also shows additional information around the data you're about to change. You can also easily look up each item individually to examine its attributes, independently of a savegame, or get other useful information that are not related to a specific savegame (but enhanced if one is loaded).
Summary
It would be nice to add select all feature to the "Words" list. In one click you'd learn or unlearn all the languages in the game.