I agree that Wrinkle in Time is sophisticated indeed (DD read the first book in grade 2 and I realized it was too early--she hasn't yet read the rest) but IDK if Harry POtter is "fluffy and simple" in the later installments. smile

I think your blog sounds like a great idea! We run into similar issues here. Action-packed, non-ruminative fantasy without a lot of internal pondering works best for DS5, though he also enjoys funny stories like Blume (same issue here with Fudge and Santa!)