Saw this post about Griffin Mountain (I am a big original Runequest fan) so I did a little digging on the interwebs.
As I was giving the module the once over, I discovered this graphic in the NPC record section. I had a thought --
When an NPC is asked to perform one of these actions, which is to say an action along the continua represented within this chart, roll 2d6 and mark the number down.
Low numbers represent a tendency toward the trait on the right, while high numbers represent a tendency toward the trait on the left. Let me give an example --
Here's a partially fleshed out NPC. In social situations, where he might need to be out going he is very likely to be INTROVERTED. When posed with a problem, he is likely to favor a PHYSICAL solution. He is very much a FOLLOWER.
If you roll a 2 or a 12 for the trait -- the NPC always acts as described. 2 = right, 12 = left.
In the example above, the NPC is always a follower and will not lead.
This is just an untested idea. YMMV. I just thought I'd share. :)
EDIT: A gentleman by the name of Alex Chalk created a random generator based upon my crazy idea. Thanks Alex!