I filed based on marriage with Russian kid. I didn't have to show income taxes or my bank statement. I just wrote down the amount on the application and they didn't ask for proof of income.
The forms I submitted in Rostov-on-Don are:
Original language certificate, notarized copy of marriage certificate, notarized copy of child birth certificate, notarized and translated copy of my foreign passport (all pages including blank ones), copy of my PRP, copy of my tax number, notarized copy of wife's internal passport (only marked pages), 2 sets of citizenship applications, 3 photos and copy of state duty payment.
They didn't ask for migration card, annual notification receipt, proof of income or taxes.