Empire have been publishing interviews to accompany the publicity drive including this short chat with Ken Stott about his character Balin:
"For a dwarf he has some wisdom. I’m not sure how much wisdom a dwarf has, but he has some. But dwarves can always make mistakes. Dwarves can get things wrong. And he gets things wrong, too. He’s the force of dignity for the dwarves. He’s worried about the whole adventure. He takes no pleasure in killing. He’s a dwarf who has seen too much of it in the past. So he does not enter the venture wholeheartedly."Which just goes to show that for all their meagre screentime, the back bench dwarf actors put just as much thought into their characters (aided by the script, of course).