You're right. They aren't all that impressive. Which makes sense to me, since a mortal and a pair of werewolves were able to kill an entire team of them without casualties. Perhaps the higher-ups in the Fomor heirarchy are more powerful.
Anyway, here are the rationales behind the powers:
Hulking Size: The second in command Fomor in Aftermath is about seven foot five. That's a little small for Hulking Size, but he needed a boost to his durability and this seemed appropriate. He should get some mechanical benefit for his size, I think. (Plus, I wanted him to have more refresh worth of powers than the ordinary Fomors).
Echoes Of The Beast: I originally intended to give them Supernatural Sense, but then I realized that Echoes Of The Beast can give sonar too. I chose Echoes Of The Beast over Supernatural Sense because I felt that talking to fish and getting bonuses to Alertness underwater were fitting abilities for the Fomors to have. In my opinion, Echoes Of The Beast is not a shapeshifter thing. I think that the vast majority of mundane animals have it.
They're both judgement calls, honestly. If you don't like them, feel free to change them.