[Anguirel]

Alcarillo, much as I worship them I would say the Sons of Feanor were mostly hot rather than cool. There are, though, some exceptions-

Curufin is cool (by temperament)

Maglor is cool (by Eomer's sea-breeze definition)

Maedhros is sizzlin(g)

Also, on further consideration, I class the Lossoth or Snowmen as not merely cool, but, in fact, chilled.