My answer is non-fighting poses as a general rule.
Here are my reasons. Interestingly 'action' figures or fighting poses are more static. Any kind of situation or diorama with fighting poses looks frozen in time, like in some Grimm fairy tale. On the other hand, with non-fighting poses (say soldiers guarding the castle gate) it's easier to imagine that it isn't static. People waiting fo the bus aren't moving much, yet time is passing. The more intense the action pose, the more frozen in time it looks. For example, a soldier falling with an arrow in his chest (I'm thinking of that gloss Britains French knight at Agincourt) looks impossibly tilted-fall already! Yet he never does. Well that's how it seems to me.
In a general way, this is one thing I like about Bill Hocker's figures, and I do collect matt figures too.