Hm. I guess I'm more conservative than I previously thought... I don't think that what you propose for comics is a good idea. If I want to see moving pictures, I go to the movies. If I want to read a story presented in pictures, I go read a comic (I like the term graphic novel better, by the way
). I don't think a hybrid would be very comfortable to read. Similarly, I dislike the idea of embedding video clips into books (with the possible exception of text books to illustrate something). Reading a book, for me, is about using my imagination to create the world described by the author. If I get presented with ready-made imagery of something, it reduces the imagination to that single image.
As for using multiple fonts in a book, I dislike that for the simple reason that it disrupts reading flow. One may get away with it for things like chapter headings, but if font changes occur in the main body of the text, I feel it's like a speed bump breaking the reading flow.
Those, at least, are my thoughts on the subject. I couldn't hold my feet still any longer