Natalie Bolton is at the top of my list, along with Abi-Maria.
Definitely would say Andrea, Phillip, Corinne and Brenda (since we are presuming that nobody has ever come back a second time) and also Parvati, Russell, Cirie and Danielle (all HvV).
Then I'd definitely include Chelsea from One World (and Kat) and Tracy from Micronesia <333
Cindy + Stephenie from Guatemala, Elisabeth from Australia, Susan + Jenna + Coleen from Borneo, maybe Candice from Cooks, definitely Crystal, Sugar, Marcus and Matty from Gabon (and Corinne, mentioned above), Natalie the winner of Samoa, Chase from Nicaragua (and Brenda of course, but I already mentioned her) and Lisa from Philippines.
That's about it from the seasons I've seen