Maybe it would be helpful to have multiple references listed for the NPCs that appear in more than one published work?
It would also be nice to have the existing portraits linked or embedded in some unobtrusive way, would that be possible?
Hm, double/triple book references would be nice. I doubt that I'll ever come around to it though, mostly because I usually use list myself when I forget a name or want to see all connected to a group or such, but after that search through all the pdfs if I need details. And backtrackning all the names at this point...
Portraits are also a good idea and much more feasible. I'll put some thought into it.