This sounds pretty good actually, but i think your idea is too overpowered and its forcing the character into a good behaviour towards the companions.
there could be rewards like in Dragon age 2 where if the companion likes you, he has an ability that helped himself and the rest of the party.
and if he hates you there is a bit stronger bonus but only for himself. i liked that very much that you dont have to be friends to everyone, and could not help the characters you dont want to.
(although the rest of the game was not that good).
