I'd suggest Kobo Clara HD/Kobo Nia. Nia is cheaper, but it has lower resolution and doesn't have warmth adjustment (orange leds). Both are able to run KOReader where you can download the books directly from Guttenberg when
https://github.com/gbnewby/gutenbergsite/issues/10 gets fixed ^_^
I own Clara HD for ~6 months, and I'm really happy with it so far.