Question: I know she's nowhere near famous enough to be Legend 12, but what level of Legend and associated powers would you give Amphitrite? I ask specifically because I have a trio of players who want to play as Scions of The Real Housewives of Olympus, and while Hera and Persephone are fine, I can't find much to give Amphitrite other than Water.
I have a bit of a secret soft spot for Amphitrite myself, so I feel you; she's a pretty excellent lady and it's tragic that she doesn't get as much love as the other ladies among the Dodekatheon. She probably isn't Legend 12, but there are traces that many scholars believe suggest that she was the original goddess of the Mediterranean, and that Poseidon's marriage to her symbolized him taking on that mantle, rather than it being something he had always embodied. Apollodorus calls her a daughter of Oceanus and Tethys, making her older and more cosmic a figure than any of the other goddesses except for Aphrodite, and she appears whenever important goddesses and female Titans are having a powwow, rubbing elbows with the likes of Rhea and Themis. Early Amphitrite myths set her as the supreme power in the sea; Poseidon's power comes from being married to her, not the other way around, though as time wore on and the Olympians became all-important, she diminished and Poseidon became the pre-eminent power over the waves.
All this makes her a possible candidate to be a Titan Avatar, actually, what with the personification of the sea and the ancient origins and the supplanting of her role by the gods, but that doesn't help you out for Real Housewives much, so we'll look at her as a goddess instead. Water is a given, but considering that she is often described as "ox-eyed" or "beauteous" and that Poseidon chased her all over the place upon first seeing her, I would say that you could give her Epic Appearance associated without too much trouble. Any other associations are slim pickings; you might grant her Animal (Dolphin) based on the myth of it being the only animal that could convince her to come back and marry Poseidon, or perhaps Epic Dexterity on the strength of her ability to flee so quickly that even one of the three crowned Olympians couldn't keep up with her. There are some archaic references to her as the "goddess of the spindle", but since there's no Spinning purview, that doesn't help us very much.
If I were going to try to shoehorn something together, I'd probably go with her having Water and Appearance at Legend 10, or Animal (Dolphin), Water, and Appearance as a Legend 11, with Dexterity or Charisma as poor alternate options if you need more. She doesn't really fit the playable roster very well, but since you're working toward a specific idea, you can probably fudge a bit and your players will run with it happily. And, as I said, she's one of my favorites, so far be it from me to discourage her use as a major player in-game!