It helps that Deutsch clearly thought through his designs with novices in mind, probably because his book is aimed at middle grade readers. The sisters have clearly different hair styles, and the older one wears glasses to make it even easier to keep them clear. Since they all dress in the uniforms proscribed by their orthodox Jewish school, my ability to keep them separate was not assured but Deutsch made it easy without seeming condescending. I enjoyed the unobtrusive vocabulary help at the bottom; he doesn't use asterisks or numbering in the pages, but anytime I wasn't sure of a word I could glance down and there it was. So all the scaffolding was there to let me just read the story.
I loved the combination of magical and personal problems -- Mirka battles angry talking pigs and her uncontrollable fury, determined to find a sword and fight dragons and appalled by her willingness to bully her brother when he tries to stop her. As an outsider, I see the see the problems with the sexism in her society, but she doesn't reject her family even as she refuses to accept the limitations they unquestionably try to impose. Feminine strengths such as homemaking skills (knitting!) are supported, even while the dangers of strict gender roles are underscored (Mirka's brother telling her fighting dragons is for boys even though there is no sign of any qualified male anywhere in the book).
My sons enjoyed this book as well -- I think they liked Mirka's quick talking that turned her knitting defeat into victory. My only complaint was the lack of place -- Hereville is clearly situation in the current time, not a distant past, but there is no indication of where on Earth the village exists.