depends on what the game targets.
If it is single player based (2-4 coop included), it doesn't really matter. More portraits/models win as I roleplay as my character looks like (as she looks like as she lived before).
If they choose to go NWN1 way to access DM tools as NWN has (and that's why NWN servers are still running and filled by RP players), well, stances is what counts. By "expression" you can't imagine just smile but whole body stance. I would point to Runescape as it is also isometric but it can express MANY moods by character posture.