It's obviously been mentioned loads but bibs and muslins to the max....but if its a present higher end/quality brands/designs would probably be a nice touch.
Liewood, Aden & Anais, Mori and lots of the scandi brands on Scandiborn are the softest and best quality muslins in my opinion.
I second the Tuppence and Crumble Star Fish blanket, YES, YES, YES to thus wonderful product!
If you're going to get toys stick to functional....teethers, sensory bits etc. Don't get anything cuddly.
Apart from metanium and a decent quality thermometer (great idea) I'd steer clear of anything feeding or bath/medicine related, you don't know how she's going to end up feeding her baby, if her baby might have reactive skin....I've seen someone mention J&J stuff.....awful, awful chemical laden crap, no one should be using this and it would be a terrible choice if the baby had reactive skin.
Overall I think this is lovely, especially if ypu follow some of the ideas on here....money to buy things is a terrible idea, just gives her more work, having someone else go out and collate some nice examples of these things would be a huge help!