Have you looked at Positive Action Bible curriculum? I don't have any experience with the younger grades, but I've used the 4th grade for my son last year, and we both really liked it. It incorporated scripture memory and songs, and he really learned quite a bit. It was a fun and interesting program, and it really made him think about Bible, not just spit out an answer.
I also have used Kay Arthur's studies for kids, and they are really great too. They're inductive, so the kids really get saturated with the scripture.
This school year, we've just been cuddling up together on the couch doing our MFW Bible readings, and reading through The Victor Journey Through the Bible, and Trial and Triumph. I love this approach because it opens the door more for discussion and prayer for us. I don't want to treat Bible reading as academic, but more as a life-long skill that my kids will want to return to over and over again.
As for Alpha Omega, I've never used their Bible, but I have used the science and history, and let me just say, BORING. I have a friend who used the AOP Bible, and she switched to Positive Action and really likes it.
Hope this helps!;)