I agree that you might be happier waiting. There are a bunch of new 9" readers coming out soon that will have more capabilities than the current ones. If you look at the
device wiki, you'll see that six of the larger screen devices are coming soon. Available font sizes depend on the reader and type of file. On my little 5", the largest font size gives me two to three words per line and I can read them from 10 feet away. My mother is legally blind (refracts at -15) and she had no problems reading larger sized fonts on a borrowed 6". The size that was comfortable for her provided about 30 words per page. She didn't like not being able to see the whole paragraph at once.
With an interest in reading current fiction, you also need to look at what formats are available for the books and authors you might want to read. Adobe Digital Editions (ADEPT) ePubs and PDFs are the standard for many of the readers these days. The perfect reader that won't read the books you want will disappoint you. It is possible to strip the DRM off of most formats, but that's something you may want to look into before committing to a device.