They did not ask much questions and did not check additional documents.
some questions they were asking:
Did you get married in Ukraine?
You do not have kids?
How did you meet?
What will you husband do in the US when both of you return?
Why are you applying for IR1 visa only now (!!!we have been married for 10 years) ?
Ok. Your visa is granted.
later I had two issues:
1. they wanted me to mail them my original birth certificate because the translation was made from a photocopy.
2. they put visa in the new passport but I have put data for old passport (all documents were done with the old passport) . I had problem getting my passport back as I had to register for the delivery using the new passport because visa was there, and I did not remember the passport data. Took a while to finally get it.