Oxford, Cambridge, York, Bristol. I'm not biased at all, ohno.
Seriously ... what does she want to do? Is she looking only at combined lanuage and literature courses, or is she trying to decide which one to do? They are quite different from each other.
I would suggest, if she finds a novel a week tricky, she may want to steer away from the language. Some (many? Not sure) literature courses would require her to read rather a lot more than that - say, maybe, a couple of novels plus secondary reading. OTOH, people do adapt and what feels scary at A Level rapidly feels doable!
UEA is the name I've heard for Creative Writing and I know its Lit faculty is strong too.
What she really needs to do is go online and look at the course specifications in prospectuses. They will differ hugely. For example (and this is just lit because it's what I know), you could find you were studying a course with a considerable amount of literary theory or with many early texts (Homer, Beowulf, etc.) in translation. Or, you might find you were required to do lots of close reading - that's when you pick out all nuances of a short bit of text in a lot of detail - but relatively little theory. You might find there was lots of provision to work in languages other than English, or almost none. And so on.
I would look at rankings, but only in a fairly general way. She's clearly good enough to apply for the highly-ranked schools, but there's no sense in her applying to (say) Cambridge if she really wants a combined lang/lit course with an emphasis on creative writing and American Lit.