FMB newbie questions

[White Owl]

I just spent several very enjoyable hours playing around with the full mission builder for the first time. Previous to today, all I'd ever done was open up other people's missions to change minor things like skins, loadouts, and maybe a different model of airplane. Now I have a basic mission in which Brits and Germans both start on the ground, meet at Dover (where else?) for a good old fashioned furball, then return to land at Calais and Manston respectively. No extra fancy bells and whistles yet, but it's my first mission built from a blank map and it's fun to play. I'm happy.

So I thought I'd start a thread for newbie questions. This way I won't spam the forum with a new thread every time I get puzzled with this new toy. Here goes.

My Spitfire squadron leader is a coward, and I don't know why. He leads the squadron to the free hunt area at Dover, waits for about a minute, then says he's returning to base. He leaves and the rest of the squadron continues the patrol and eventually gets into a fight. The problem is intermittent, though. Roughly a third of the times I've tested, he'll grow a pair and stick around to fight. Right now all pilots in the mission have straight average skills, so I know it isn't an issue with the discipline or bravery settings. What causes this problem, and how can I fix it?

Speaking of those individual pilot skills, is there a good way to randomize those to get more interesting/unpredictable behavior? Right now I'm thinking of just rolling a trusty old D20 over and over again, unless somebody has a better system.

Thanks for any advice for da noob.