I do not agree in that part of your thesis that in most party games the companions do not challenge the leader's decisions and perform the function of the interactive appendages of the protagonist. They have their own history, their views, they value some decisions and despise others.
Sure they do. They bitch and moan ... and then fall back in line. It's a good way to create an illusion that your choices matter, that your party members care about your decisions.
Yes, there are different party games from different developers. But to argue that all these products are typical - it's just not right.
They are typical in a sense that party members were a sacred cow from day one. Their first and foremost goal was to fight battles and provide abilities the party needed, not to have opinions and the will to act independently, which is understandable as we have two conflicting designs here:
- a perfectly configured fighting squad where a loss of a specialist can ruin your entire strategy and thus shouldn't be an option
- a group of people with their own preferences, beliefs, and agendas.
In any case, any leader should be a diplomat. And if he gathers people around him, no matter who - paladins or murderers from the big road and they do one general thing, he has the skills to unite people through the search for compromises.
Is that how it works in real life? Would a diplomat/leader be able to talk down a religious fanatic? Convince a "murderous psychopath" not to act on his impulses? Convince a lawful good paladin to let a lawbreaker go? I have my doubts.