I'm fairly new to all this, but from my experience 3 deg caster should be enough for the front end if you're running on asphalt.
If you need more camber you can use static camber by adjusting the front camber links. Just don't forget that this will add to the total camber the caster blocks provide. Someone correct me if I'm wrong here.
I've tried using swaybars but not had any luck with them, but then again my car setup was wrong. I believe not many drivers use these on asphalt....not sure about carpet. Sway bars can be used to cure understeer or oversteer depending which end you put them on (front sway bars for oversteer...rear for understeer).
As for the wheelbase...I would try to fix whatever problem is on the car with other settings (droop, ride-height, tyres, roll-center, shock oil) first before adjusting the wheelbase. As you probably know shortening the wheelbase will give you more weight over the rear axle. Depending on the weight distribution of your car this could help because the FK'05 is a little front heavy.
If you are racing on aphalt you can check out my latest setup sheet
http://www.teamxray.com/xforum/xform/in ... tup=t1fk05
Don't worry about my placing....just had a bad day...but the car handled quite well. See comments at the end.
Cheers,
S