I'm currently working on part of an extended sequence in Cloud 109 where Gina, Cary and Rabby appear in their real world guises and for this to work as a contrast to their zany avatars I've endeavoured to make them as real as possible, in the case of Gina she is very definitely modelled on a real person - Sheryl - you're a star! The advantages of this strategy are that creatively speaking you are reaching out to the world beyond your drawing board and using real people and locations to add extra conviction to your storytelling, the disadvantages as cited previously are that you become so enslaved by your source material that you lose the necessary objectivity to make the panels flow with assurance and conviction.
So a little bit of both reaching out but drawing (the pun is intentional) from within is required. There comes a point where having looked at all the photos you just need to get back to drawing, but here's the trick - having looked at all that reference and absorbed it into your subconscious it should then inform your drawing.
This is pretty much where I am with the page I am working on at the moment, I need walking figures to add in here and there. I could just trace them but there is for me always something a bit lacking if this is done to excess (and I'm already into dangerous waters as it is on this page) so comes the moment to get the scrubby old red pencil and just loosely draw what you feel and don't make it too specific.
What you're trying to do is produce something that will act as a trigger for all that information previously stored in your subconscious, almost like looking at a stain on the wall and seeing all kinds of dramas contained within.
There's a bit of guesswork here and there but I can already feel a certain lift as I look at these little scribbles - they have the spark of life - the figure with his back to us in the yellow top might yet have to go.