I haven't read all the posts, but here where I live in the States, I think the HW has really gotten out of hand! Two pages of math plus reading and spelling almost every night for a 7-yr-old? Math, "English language arts," vocabulary (separate from the language arts HW) and reading almost every night for a 9-yr-old? Fortunately, my DGC are bright children, but the little guy has already begun to resent HW. And, IMO, it's crazy!
Frankly, Tessa, my first inclination, if I were a young mom and my 6-yr-old resisted doing HW, I would let it go, for a while/let her decide if she wants to do it or not - see if the teacher even complains. With the pressure off, she might even choose to do it sometimes.
Well, unless it's going to affect her in a bad way, like not being promoted (or whatever the word would be in the UK). Then I agree with the idea of sitting down with her and maybe, taking turns giving answers or whatever gets her through it.