I'm in Act II, but what I'm refering to is the Merchants and NPCs, not the companions. I should have made that clearer.
For instance if I am rude to a merchant and he doesn't like my tone, it would be fun if his attitude would decrease, instead of remaining the same. Or for instance the dwarf in Fort Joy knows Lohse and they get along very well,
he even gives her a present
, so it would only make sense if his attitude would be higher towards Lohse than towards the other characters.
Pretty much the same mechanic that is already in the game when you attack an NPC (I believe in that case the attitude drops by 20) could be implemented in dialogue, just not that extreme.