So I'm guessing you've got Welsh connections!
I like Gwilym, the pronunciation's straightforward, even though others may initially struggle with the spelling (Tough! They can learn).
I like Ruben (I've only ever seen the "Reuben" spelling here; is there any particular reason you prefer the Spanish way?). Again, pronunciation self-explanatory.
I like Rory. Gwilym Rory, perhaps?
Girls-wise, I really like Arianwen. So pretty. And Ari's quite a cute NN. Although it's not that familiar, it's easily pronounced and, actually, the spelling's logical.
Ffion's also nice; I guess your DD would get used to reminding people it's double F! (I never knew it meant "Foxglove" until looking it up just now...every day's a school day 
)
Ruby and Iris are both lovely. Pretty popular, if you're bothered by that sort of thing?
Arianwen Iris gets my vote.
Europa is a name that would definitely attract attention: could really suit a very confident, outgoing, quirky kid (am thinking perfect for budding actor/ singer/ writer) who could 'own' it. The Greek mythology background's interesting.
On the other hand, a less extrovert girl might struggle. The only NN is "Ropey" (and potential for lame Brexit jokes from adults?).
Hope that helps a little...Best of luck for a safe and speedy delivery 