That's an awful lot of work
I'd be willing to spend that time for a very important NPCs, someone central to the plot.
Problem is, most of my player windows have this issue. Another example is a puzzle I have, "Entrance to the cultist temple". I need that info for organization purposes but players are not supposed to see that it's an hidden entrance to a temple.
And the list goes on ...
Not to mention that, what if players meet Sabella elsewhere than at Rose's Bar ? (you know how players like to wreck the GM diabolic plans).
The more I think of it, the more I think I need to be able to reveal an image without revealing its description.