I agree with you Clephas. I'm a fan of sports centered animes too (same as Overkill : Kuroko no basket, baby step...) that's why I enjoy it. There are not many Vn on a sports theme. I mean with a large amount of details and not just a stupid sport setting in the background with a lot of ichacha heroine/protag.
Personally, I prefer Ao no kanata over Walkure which is not bad. In my opinion, ao no kanata is more intense (emotionally). Anyway that's what i felt .