@Indira
Yeah, it could be as simple as that. I really hope one of the Larian folks take a look in here and comment on it.

@Merendrious
Exactly. It would be too obvious to just kill off your party members to get them back to full health before the next battle. So I completely agree with the 1hp/1mp when resurrected.
Personally I think that if you keep hitting your party members with harmful spells/whatever then they should eventually leave you. (And of course make it harder/more expensive to hire replacements)
I'm not quite sure how to handle it between the 2 main characters though. Especially not when you have full control over them both. Though I think something that could be used as a solution has been mentioned, getting bonuses/penalties depending on the relationship of the main characters. This could be used to penalize the player for killing off/harming the main characters all the time.
Of course, this could be a setting that one could choose to play with, as to cater to everyone. (Some probably wouldn't like being penalized for throwing fireballs all over xD)