In single player I think it would be good if all party members could chat. One suggestion I would like to make is that when conversation window starts the pictures of all party members show up on the left hand side. You can then click on a party member picture in the conversation to allow them to interject.
Example:
Player party with a,b. A starts talking to npc1. The conversation window then pops up:
npc1 -> blah blah blah
a -> can i help
(at this point if you click on b in the conversation window)
npc1 -> yes yes yes
b-> why should we help you're not a lizard
a-> I would be most cheerful to help a fellow elf
npc1 -> spits on b; and thanks a.
