Found a good answer to my question:
Some gear also has Light/Dark requirements. For example, a Light Side Jedi (with Light I or higher) cannot use a red color crystals in his weapon unless it is already equipped in the weapon, and the entire weapon has no Light/Dark requirement. The Light/Dark system is tied to conversation choices, and has extremely minimal impact on gameplay beyond cosmetics. That is to say, there is no item it the game without an alternative that is identical in stats in the event it has a light or dark requirement.