I realize that this would be messy to implement, but I will describe it anyway.
One of my favorite Scrivener features is the ability to color code the scenes. I currently use color-coding to show me the status of each scene (to do, pseudo code, first draft, revised draft, final draft).
That way I can see at a glance how much work I have to do.
The problem is that I can only choose one system of color coding. It would be nice to use the colors to show the different subplots. Or, they could designate the viewpoint character for each scene.
Scrivener would have to allow multiple labels sets, and allow the user to choose to display the color coding for each of the different sets.
I came up with one trick: I use a special character to indicate a scene featuring the main character. That helps me see at a glance how those are organized:
I use Collections for achieving the same things you want with the presence of characters in a scene. Each one gets added to a Collection. Documents > Add to Collection or right-click contextual menu. Similarly for locations. Also scenes with discrepancies are added to a collection. (I also use Annotations embedded in the document text and have Scriverner links that refer to the relevant documet(s). I select the appropriate collection in Scrivenings mode to check all these things out.
I use Icons where you use a weird glyph. The thought bubble means the document needs more work, red flag means there’s serious issues in there to be resolved. In one project I used the eye … but can’t now for the love of me remember why but it clearly has a significance I wanted a visual reminder about. Documents > Change Icon or right-click contextual menu.
I only use the Mac version so YMMV. Heck I only use Mac period. How far the Windows version lags behind the Mac one I’ve no idea but KB has said it will eventually catch up.
You can also use the outliner for this kind of thing, instead of trying to cram it all into the binder. If you’re working exclusively in the manuscript folder, you can even hide the binder to give the outliner more room, and set it to open whatever documents you click on in the “other” editor.
Once you’re using the outliner, you can create custom metadata fields for each plot, color coding them so that they stand out when you mark a given scene as belonging to one or more of those plots/subplots. When combined with custom icons and coloring those icons with the label color, you should be able to cram in a lot of color-coded metadata into each outliner row.
