I'd point to something like Feedbin's ability to pull remote content from the subscribed site, then. No idea how well it works on something with an e-ink displ

I'd point to something like Feedbin's ability to pull remote content from the subscribed site, then. No idea how well it works on something with an e-ink display, though. You might look whether anyone's made a stand-alone RSS client aimed at offline reading that has that ability.