the covers look better. The pages we look from a side is an interesting idea, but there is one problem. They look too new. Remember, that this book was once manufactured by hands, thus it is imposible for the pages to look so perfect, they would still look somewhat clean though. Later on it was used for a long time for sure. Hands are dirty, with pot, and everything we touch. The pages must reflect that. unfortunatelly i'm not sure if you can have the effect with the UV face layout in the way how you did it.
As about the jpg. It can't have perfect quality. It is impossible, no matter what options you use. Maybe you would have perfect quality, if there was zero compression, but then it is pointles, because it would be same as bitmat.

Also, i would advice you to do your U map like this: The green is not used space, since we don't want to see the color of the pages on the red cover, when looking at the book at high angless. So i suppose the not used space should e from one side color of the pages and from other color of the cover.

EDIT: resize tool is doing fun stuff with images

look at which direction the page lines are on my image and in which direction they are o the original
