Scarlet, Rory or Rufus would be cute!
Girls - I like Sara too (but the mispronouncing as Sarah would get annoying) - I like Sarah but it’s quite staid compared to Rosie and Ruby - you could use Sadie as a nn for Sarah?? Or Lara, Zoe, Lauren, Luella, Phoebe, Chloe, Stella, Clara, Cleo, Juno, Arran, Erin
Boys - I think Aaron goes well, or Oscar, Hugo, Milo, Jacob nn Jake, Jackson, Ethan, Evan, Lucas, Samuel nn Sam, Nathaniel or Nathan nn Nate, Christopher nn Kit,