Are you going to have your players create characters only from F&D, allow them to build what ever they feel like playing or require a mix from the different books?
Beta test character load-out
I'm going to encourage them to mix it up...to get a good Beta Test feel, one should incorporate other careers into the setting, IMO. I'll be starting them at Knight Level to allow for a more "developed" feel.
I'm heavily considering running with pregens of my own design, but I guess we'll see what happens when I get my players together