US Immigration from Taiwan

How can some I-751s sit for a long as 3 years (No RFEs) before processing while newly-submitted cases are processed in a little as 3 months? I think USCIS is manipulating their processing times by processing cases last in, first out....at the expense of people who submitted cases earlier.

Anyone have a better explanation? Local office issues?

I've deleted about 50 spam posts....

I'm US citizen, been living in Taiwan for almost 4 years with my wife.

Working on my i-864 for a CR1 visa.

Here are the ways I will be proving domicile in the US. I'm wondering what specific documents I need to show for these.

1. Maintained 2 bank accounts with 1 credit card that has been actively used.

QUESTION on this - can I just show a screenshot of my online banking accounts and credit card statements? Or are they looking for something more official (not sure what that would be, maybe a documents I could request from the bank)?

2. Maintained permanent US address.

QUESTION - Is just a picture (or scan might be better?) of any letter sent to that mailing address sufficient? It is my parent's house by the way.

3. Voter registration

QUESTION - Unfortunately do not have a voter registration ID card. On the state of MN website (mnvotes.sos.state.mn.us) I am listed as registered to vote. BUT, the website is setup so that when you hit enter after typing your name, it shows that you are registered and where you are registered, WITHOUT my name on it. So, not too helpful proving that it is my. Is there another way to show that I'm registered?

Thanks for the help everyone.

We just received my wife's passport with the temporary visa stamp (sticker) and paid for the $220 USCIS Immigrant Fee.

Which address will the physical green card be mailed to?

Is it the address we entered in Form I-130 #12.a. or the Permanent Address listed in our DS-260?

Filed I-130 for my wife, she's from China, she did graduate school in Macau for 4 years. She already has her Chinese police certificate, does she need one from Macau as well?

Macau is Chinese territory that's kind of autonomous, and no one in China would consider Macau to be a different country.

Also, during her time there she would regularly go to Zhuhai, which is in the mainland, and did it almost weekly. So there was definitely no time where she's in Macau continuously for 12 or 6 months.

Thanks.