I have also begun to UV map part of the model to test out the application of Textures. My concern is not mapping them correctly to exactly match the original artwork. But I will do my best to match them as closely as I can.
I'd been toying with the idea of bump mapping the texture of the small pieces of paper used to make the collage. But I personally feel it looked better without a bump map. I also think it looks better with a surface shader over a lambert.
Lambert shader Lambert+Bump Map
Finally I had a bit of a brainwave about the eyes and how they could blink another way. I don't like the way I've built the eyelids, I'd like the eye to appear perfectly spherical from all angles which is currently not what I have achieved. So I've tried out a method of interchanging two separate eyeballs, each with a different texture. It would be simple to create a control to toggle on/off with its visibility.
(Above: Eyelids that I don't believe have worked well. Especially when seen in profile.)
This version does have a more cartoony nature about it. but it could possibly work better.
(Above: Pure spherical eyeballs that switch between an 'open' texture and a 'closed' texture.)