We almost seem to be going in circles. The reality is, right now, what we want is to be able to go from Pages to ePub directly. But we can't, yet. What we can do is use InDesign, and go straight from InDesign to ePub. So we do have a DTP solution for eBooks and tablets presently.
And let me say a few more things about PDFs. I like PDFs. Their good for a lot of things. Reports, proposals, resumes... but books? PDFs are limited and very slow to pan through. Also, what they aren't good for is when you want to convert them to be read on eReaders. They just aren't. I've converted many of them with Calibre as well as using Sony's eReader software. The results are very mixed. And Sony's eReader software is considered to be the best in terms of how it reflows the text and graphics in the PDF.
Again, what we have to realize is this is a new medium, and it demands new interfaces and new book and publication designs. To think that you can take an 8.5" x 11" document, that is in PDF format, push a button, and have it look great on a tablet computer is really simplifying things.
Let me give an example of what is happening in the publishing industry. Digital magazines have new layouts for tablets. And a lot of them have portrait and landscape layouts. They change based on the orientation of the device. This is a lot of work for the production team, and expense. But in the end, there really isn't a choice. You will have to reformat and redo your books, if there is any sort of complexity, so they look good on tablets. Having to zoom in, or enlarge, that can get frustrating and impede the reading/educaitonal experience.
Right now, the solution is either go from Pages to a PDF and Calibre, for example, or just use InDesign, and export straight to ePub from there.
And about just reading PDFs in an app, or reading PDFs as books. Honestly, PDFs are a pretty bad reading experience in the context of books. The iBooks App is amazing. It's the best digital reading experience available. It's nothing like a vertical, linear scroll through a PDF. It's way faster, the text is completely clear and uniform, the graphics look great, and it automatically changes based on the orientation.
We should be happy a lot of that hard work has been done for us. ePub really gets a bad rap and it shouldn't. Imagine if there was not standard, no ePub. Imagine having to convert from PDFs, and that was the only option. Or that we were all stuck reading PDFs as books. PDFs are simply not meant to be used in the way people are implying.
I work with PDFs daily, in communications. Some complex, and I use Adobe PDF Pro, etc. I have every OCR program available too. Anytime there is any complexity in a PDF, converting it to something else is simply a nightmare.
My vote is for ePub, which can be dumped straight into the Kindle Store, the iBooks Store, and pretty much every other eBook retailer's store. It allows for inline graphics, images and text. And InDesign goes right to it. This is not a case where ePub format is worse than PDF, and that it's just a trend of people and business that have accepted ePub format. PDF is the lessor of the two. If it really were better in terms of it being able to be easily converted into formats readable by dedicated, universal eReader software like the iBooks App, there is little doubt that companies like Apple, and many self-publishers, would just stay with PDF.
But this is not the case. The fact is, graphics just simply don't come out of any PDF well at all, even using the best OCR software. I don't see how any eReader software is going to do any better at this in comparison to expensive OCR software that has been around for decades.
If you just have a simple book in terms of it being pretty much all text, than PDF might be ok to convert from. But still, there are going to be formatting issues. My advice, therefore, is to simply stay away from PDFs for book publishing.
Sony eReader software:
http://ebookstore.sony.com/download/