The Fëanor inside Fëanor Sons

[Lalaith]

Caranthir
Is there any more to him except being haughty and ill-tempered?

Well, yes there is. He behaved well and honourably to the People of Haleth, offering Haleth recompense for her dead brother and father. He saw "what valour there was in the people of the Edain." This is at a time when many of the elves (Thingol and the green-elves of Ossirand in particular) were inclined to despise them.
I do not think that Feanor would have had much time for Men, one of his greatest flaws was arrogance. So perhaps even Caranthir, so much his father's son, had something of his mother in him.