I also love books.
I just don’t think I have what it takes at the moment to tackle such a task, the pages just look so intimidating, even if I understand most of it once I start reading. I guess it’s a problem of perspective.
I’m studying for N4 at the moment and, while it seems like it won’t be a problem, I tend to suffer from a lack of confidence, instead of believing in what I’ve been studying for years.
I would be overjoyed to one day be able to read 春木村上’s novels in Japanese, but I think it’s better to focus on what I can do right now, and work on it little by little, instead of perhaps losing motivation once I see how much I really lack if I tried to read a normal book. I seem to think that way, even if it’s sort of counterproductive when learning a new language, and I don’t really know how I got this far. 
That’s why manga, where I get most of what’s going on and only miss specific grammar points or vocab, seems to me as the best option. Probably because it’s stand-alone compared to a book, but I guess you could see the book as chapters and work on that. I guess I could give it a try sometime.
I guess, to me, manga is reinforcement on what I already know and learn in class, and a book would be learning new things, or something like that?
I’ll try to hold myself accountable to that.
Also, /rant.