Currently fields are at Document Level, changes made to these fields are visible to all Users,

In the case, where a user is working through a large query spanning multiple documents, it would be nice if we could avail a user-only fields relevant to that user only, where they could add a comment, or simply flag the document in a result list, then later be able to search/filter on these user fields. Values for User A would not be seen by User B, and vice versa. Once done, have the ability to mass reset flags in a result list.

I suppose a Table field could be added, each user adds a line, for their own use when needed, however this is visible to all users viewing the table index for the document.