http://www.armageddon.org/general/noble.html
Anyone know if there is more about bastard nobles to go on than just this?
If there's not a lot there, there should be. Having played one, I gotta say it's probably one of the most fun roles I have ever had.
Having played bastards as well, I would say that yes, it is quite an enjoyable experience. You get a good amount of immortal support, and there's almost always something you can do... you're free to roam whatever estate it is that you're partially blooded to (in most cases), and you're free to go off and do pretty much whatever you want as long as it's not too extreme or stupid.
Think of a snobby rich kid with power armor, or a gun with an endless clip. Abuse your station, enjoy your role.