Index as I find a record in unindexed catalog film.
As an example, I have a lot of Presbyterian ancestors that were in congregations in Pennsylvania, then many moved to Ohio, then many to Iowa. As expected these families intermarried, and gathered in the same congregation, or related congregations. Presbyterian session books have been a great resource to me in connecting immediate, or extended families.
As an aid in my research, I've created spreadsheets from different FHL films in which I've created my own index of names that I know could be related (if I'm related to one Wilson future research will reveal that I'm related to other Wilsons). As future research leads me back to people that may be in one of these congregations I check my spreadsheet that will show me the image number(s) for entries for a particular person.
As it may be some time before a particular film (film meaning any format) is indexed, it might be helpful to others if I could "index" a person, of group of people, as I find them. It might help patrons researching people or families contained in that record, even though the entire record hasn't been indexed. Also, when a particular film comes up to be indexed, those previously indexed entries could be skipped, or just included in the review process.
If this is a bad idea, I'll remain anonymous, if you like it, Maury Dean