Tamsin, definitely.
Tamsin is sweet and down to earth.
Naomi is light and a bit insubstantial, despite its long history, just the sound. Also
Naomi is very
Naomi Campbell to me even though I've met many, especially in England. I don't like how it says 'I moan' backwards, I don't like how it means 'Hey, granny' in
German (yep, really) and I don't like that it ends in an -i. As far as I know the Bible story wasn't that great either.
I really like
Tamsin, it's unusual and
Tammy can be a cute nickname.