The I-751 instructions do state to write "N/A" when a question doesn't apply, or "none" instead of zero. My understanding is that they are now less strict about checking if N/A is written for things that are clearly not applicable.
The instructions also list the initial evidence that you need to submit.
The only "required" document copy is that of the front and back of the permanent resident card. If you feel like the other documents demonstrate your family relationship (such as drivers licenses with matching address, passport stamps with the same date, etc...), then it'd be beneficial to include them.
The instructions also state that specific evidence is required if a spouse has died, in event of divorce, are abroad on government orders, or if you've been arrested or detained by police (traffic citations without alcohol/drugs don't need to be mentioned).