It is a good name; I spell it
Rachael because
Rachel, where I live, sounds like RAH-Xel, with X standing in for the throat-clearing sound.
Rachel Sophia would be my choice; possibly also
Rachel Serena.
Rachael Susannah would be too biblical for me; perhaps not for you;
Rachael Suzanne would do nicely, as would
Rachael Suzette.