For 'tomorrow is a long time', it gives a sense of the expanse of the future. It might make one think about all the things that could happen over that long stretch. Regarding 'every picture tells a story', it's about the idea that visual images are full of information. If we think about how these two statements relate, in the long tomorrow, the pictures we create or encounter will be carriers of the stories of our future experiences.
Well, from 'tomorrow is a long time', it could imply that there are a lot of possibilities and uncertainties in the future. And 'every picture tells a story' means that each visual representation, like a photo or a painting, has a hidden meaning or a narrative behind it. So perhaps, combined, it could suggest that in the long time of tomorrow, all the things we see (pictures) will have their own stories to unfold.