A question that has been asked several times here
. .. and I've replied several times as well.
Eink readers aren't good for Manga, tablets are, and 10 inches. Why? because the dialogues. 7 or below is too small so you must rely on zooming features which in my opinion makes the reading experience a painful one. And because the way eink works, reflowing ot zooming takes longer than LCD technology, due to refresh rate.
Is doable in 7 inches and eink, but if you're going for something small, a tablet gives color and faster experience.
eink is for reading, in my opinion .