A parable or a knife?

So once again, here's the current primary-source list for my post-apocalyptic and dystopian novels course (now titled "Coming of Age at the End of the World"). I dropped 1984, but reread The Giver this week — it really is the archetypal YA dystopian, Christ imagery and abrupt ending and all.

The Giver, Lois Lowry

Riddley Walker, Russell Hoban

The Knife of Never Letting Go, Patrick Ness

The Hunger Games, Suzanne Collins

Battle Royale, Koushun Takami (film)

Feed, M. T. Anderson

How I Live Now, Meg Rosoff

Never Let Me Go, Kazuo Ishiguro

Moon, Duncan Jones (film)

I'm trying to nail down the book list so that I can submit it to the Wooster college bookstore, but I'm stuck on one final decision — whether to take out The Knife of Never Letting Go, which pairs with Riddley Walker, and swap The Parable of the Sower into its place. There are elements of TKoNLG that I'd really like to discuss, the book's engagement with gender and masculinity being the most obvious, and I wish Parable were a little shorter (and better edited). But I think the scope of Butler's book matches up better with the scope of Hoban's, and I'm leaning toward including it instead. Thoughts? Opinions?

Really what I need is another month in the course so I could teach TKoNLG along with His Dark Materials (and not just because they both have knives in their titles).