Janh - earlier you asked "roisin, who do you mean by the kind of children who most need encouraging to read are exactly not the kind of children to whom JW novels appeal"?
Briefly: girls! But to expand a bit ... 8-12 yr-old girls, who are very fluent readers.
It's great that your ds2 has read her books though, and hasn't been put off with her image as a "girly" writer.
I do have problems with the subject matter too. I agree completely that the titles/covers are not differentiated as to which are more suitable for younger readers. And things like Lola Rose are regularly read by 8 yos, and I think that's unacceptable.
Maybe I'm overprotective, but ds1 is a bit of a worrier, but is in a stable family background with two parents. I don't think he needs to read about children in care, or children whose parents have split up, or children who've experienced domestic violence. OK maybe it's good for children who do experience those things to read about it, and for teenagers to develop some understanding: but not for primary school children, I think. And it is primary school children who are reading her books.
I don't object to writers addressing these issues, I'm just not comfortable with the age-range of the children who are reading it. Does this make sense?
Malorie Blackman writes excellent books about racism: but the covers, the blurb, the classification everything about them puts them firmly in the Teenagers section. Similarly Garth Nix's Lirael books, which deal with necromany in some depth: because of the way they are marketed they do not appeal to junior school children (even if they're very fluent readers), which is great because they're not appropriate for juniors.
IMO many JW come into the same category ... or should do. But they don't. And it makes me cross.