I don't quite understand. When you request for fee waiver, you'll have to file paper version which means you don't need to attach a check or your credit card info to the application. How could USCIS possibly charge you the amount of the application fee?
About state ID, I can only speak for Georgia. It does take about a month to receive a state ID but they do issue a temporary paper ID on the spot that's valid for about 30 days.
Agree. But there are other scenarios where you may need your naturalization certificate other than applying for passport, such as when you are applying for green card for a family member or when you are applying for a gun license as some states require it. So it's a personal decision whether to replace it or not.
I think removal of your middle name is a legal name change and you need to file it on N400 form or request it during the interview. Either way, you will need a court order from a judicial ceremony.
"If you have dependent children who acquired conditional resident status on the same day as you or within 90 days thereafter, then include the names and Alien Registration Numbers (A-Numbers) of these children in Part 5. of Form I-751 in order to request that the conditions on their status be removed as well. If you have dependent children who did not acquire conditional resident status on the same day as you or within 90 days thereafter, or if the conditional resident parent is deceased, then those dependent children must each file Form I-751 separately to have the conditions on their status removed."
If your stepdaughters acquired conditional resident status on the same day as your wife or within 90 days thereafter, then you may include them in the form as dependent children.
"The filing fee for Form I-751 is $505. A biometric services fee of $85 is also required for petitioners. Each conditional resident dependent, eligible for inclusion on the principal petitioner’s Form I-751 and listed under Part 5. of Form I-751, is required to submit an additional biometric services fee of $85, including dependents residing overseas pursuant to military or Government orders, regardless of age"
Both your wife and your stepdaughters need to do the biometrics if they are included. Dependent children do not have to pay filing fee but they need to pay the $85 biometric fee. The cost for your wife and two stepdaughter should be: 505+85*3= $760
Good luck!