I'm having the exact same predicament with dd2!
Dd1 is Vivienne. I think Claudia goes slightly better with Vivi, but I think both Saskia and Claudia go beautifully with Naomi. In my head Claudia is a little classier but Saskia is more glam/feistier.
Have you thought about middle names? I have a middle name I love that goes beautifully with Saskia, but can't think of any that work really well with Claudia.
Also prefer Saskia's meaning (Saxon woman) to Claudia (lame). But then I'm not really bothered about meaning.
Saskia is rarer in the uk (600ish) I think Claudia is around 200 or 300. I like the fact that Saskia is less common.
Both have fab nicknames - coco for Claudia or Sassy/Suki/Kiki for Saskia.
I think maybe Claudia just edges ahead for me, despite all the practical reasons for preferring Saskia!
I realise this is really unhelpful sorry! But I understand your predicament and actually you can't make a wrong decision here because they're both FAB.