The general suggestion is that in a handout you could add more hidden sections like the current gm notes. You would be able to add and give individual permissions to players for each section just as you would a handout. This way, as an example, you could have a handout describing a certain person or place. There is the general knowledge that it is okay for everyone to see and know, then the gm notes only for the gm, but in addition the you could add extra sections to give particular players extra insights or knowledge. Those whose backgrounds give them additional information that the rest of the group wouldnt know. The upside of this would be not having individual messy handouts for that information. It would be organized under the relevant topic/place. Would do wonders for organization and ease of access for player and gm.