I have two Kindle Fire tablets. They're very versatile, and I like them very much (and they cost much less than iPads). They're lighted, and I understand you don't want a lighted display. But the display can be adjusted way down, so it's not too bright for you.
I use my Kindle Fire tablets mostly to display PDF files, and they do the job very well. I load all sorts of need-to-read things on my Kindle Fire for travel.
-Joe-