Talk to the immigration lawyer you have been working with.

Based your information you should not need a cosponsor. Good Luck

Can the daughter file a petition to get her dad the green card faster or can i file for him fast so the family will be tighter.

Once your niece turns 21 she can petition for her father and the wait time would be much less than you sponsoring your brother.

please see http://www.uscis.gov/humanitarian/battered-spouse-children-parent One has to have an approved I1360 prior to getting work authorization

Can anyone help me in creating response for L1B visa extension RFE ?

You should talk to your company's immigration lawyer or can see independent advise also.

Did I do this correctly?

At this point wait to hear for a decision. If they require more information, they can request for it. It does always help to have a letter from the...

I-94 Extension after passport renewal

Please talk to your company's immigration attorneys.

H1B Transfer Before/After I-94 Expires.

Talk to company b's immigration attorneys as the are the ones who would handle your paperwork.

Could I apply for US citizenship after 4/29/17 (3 months ahead)?

Consult an immigration attorney before you rush to file. You need to provide all the facts and the general form is not the place for specific answers.

Is it true that N400 applications are not placed inline for interview if not within the 30 days of anniversary date?

You can file at the 2 yr 9 month mark but only become eligible at the 3 yr anniversary.