I don't have a "real" ebook reader either, but I'm an avid reader of ebooks on my phone, so I checked out your map on the phone. I agree with Djekspek that the trees are much too dark, I'm looking forward to seeing your new brushes The size problem, at least on my phone (and I think it will also apply to kindles/nooks/etc) is not as much how big it is but the aspect ratio is making it hard to see the whole map. If you check out TheRedEpic's latest map (here), that one has a perfect aspect ratio (as in pixels wide divided by pixels tall) for my phone and I would bet it's good for eInk readers too.