I like to suggest a vital improvement to the built-in voice chat feature: Individual volume control for each of your party members.
In my experience, most people come through very quiet even after they turn on mic boost. I can circumvent this by turning all of the game-related audio to 0.10 or so, then turning up my speakers so I can hear them over the clangs and crunches of sword against skull. Of course, this doesn't work if someone else in the party does have adequate volume.
Please, add a volume tool-tip to the party right click menu, and give us plenty of leeway to raise them well above the game volume if necessary. I'd rather hear them with some clipping than not hear the rogue say "Trap" at all!