Everyone is more or less spot on. Also, ever since you fucking reckt that commisar, I've thought of a way to balance the system because stacking bonuses are OP as fuck.
Combat: Having a weapon, no matter how good or shitty, is +1 to attacks. Shitty weapons have a chance to break if you roll natural 3 or less. Good weapons usually have some other benefit.
Having two weapons and dual weilding will not give +2. All it allows is to reroll when you roll a natural one. Also, if you ever get disarmed, you still have your secondary weapon.
Rolling a natural one will cause that weapon to break. If you rerolla and STILL get a one then your secondary weapon breaks.
Defense: You roll against your opponent. If they roll higher than you, you take Damage. If they roll lower, then the attack is deflected. If the enemy rolls a natural 6 and hits, you get two Damage. If you roll a natural 6, you can counter attack.
Armor gives +1 to rolls. Same as weapons. If you roll a natural 1 in defense, it breaks.
Health: You have four states of health: Healthy, Damaged, Critically Damaged, and Fatally Damaged. Healthy is what you are at right now. Damaged gives -1 to particularly difficult tasks. Critically damaged gives -1 to all rolls. Fatally Damaged is your last chance to heal or die.
Other bonuses: Stuff like intimidation and karizma don't stack anymore, only giving plus ones. However, each additional thing that grants plus ones grants a reroll. Also, you are able to safely command the total amount of plus 1s times 5 number of followers (excluding grots, as part of your Runtherd buff)
Things I have to work on (and need your help):
Teef. How much is something worth.
Will update this list.
Tell me if I missed anything you feel important or unbalanced.