While I've never been fond of
Eloise or
Eloisa, I just love Héloïse (this spelling only); so I'd give it a 9 or 10.
The Héloïse I know is called Héloïse
Hortense (French pronunciation).
Peronally, I rather like Héloïse
Margot and maybe Héloïse Adèle, not sure about the latter, though.