From your list I like [name_f]Caprice[/name_f] & [name_f]Mayla[/name_f] the best. I’m not keen on [name_f]Perla[/name_f] or Saorise personally but they aren’t bad names just NMS.
First names that came to mind when I saw [name_m]Marcel[/name_m] were [name_f]Eloisa[/name_f], [name_f]Cleo[/name_f], [name_f]Nia[/name_f] & [name_f]Anya[/name_f]
[name_f]Caprice[/name_f] and [name_f]Perla[/name_f] stand out to me — subtle sound connections to [name_m]Marcel[/name_m], but not matchy. Meaning-wise, I prefer [name_f]Perla[/name_f].
Not a big fan of [name_u]Sloane[/name_u] or Sersha (I think it would still be mispronounced).