US Immigration from Cambodia

I'll be using a well-qualified joint sponsor for our K1. I have a few questions.

1. On the i134 (Part 3, #1), the only options are "employed" or "self-employed". If my joint is retired, do we check "employed as" and write "retired" in the box? (On the i864, it has a "retired" option)

2. i134, it asks for income and asset information. Is the asset information necessary if the income is above the minimum requirement? (On the i864, asset is not required unless income is too low)

On the instructions, it says "As the sponsor, you must show you have sufficient income or financial resources..."

It also says "Submit in duplicate evidence of income and resources, as appropriate"

So does this mean that assets MUST go on the i134, or only if income is not great enough?

DS160 - Question "Person/entity paying for your trip"

Not sure what to make of this one. If my beneficiary pays for the trip to the US (should we be approved), I feel like it looks as if I'm not supporting him. If I pay for the trip, I feel like it looks like he's using me for the money. I don't know how they look at these answers or what the right thing to do is.

Several times while flying around Asia, I would try to check in online or at a kiosk and my reservation would be "frozen". I had to physically show the card and my passport to an agent before they would check me in. I asked about this a few times and they always said they had to physically see the card to verify it wasn't stolen. If I buy him a ticket and they do this, he won't be able to show them my card because he won't have it. One option is he pays for the trip with his card (so he can show it if asked) and I reimburse him when he arrives. He could explain this situation if asked but I'm not even sure how much this issue matters. Are we overthinking this?

We submitted a heavy petition with alot of high-quality evidence: we lived together for over a year with a lease, traveled to several countries together, and proved it all with solid documentation and a few pics to back up the evidence. I feel we have a pretty solid case and we received no RFEs. It appears that the NVC only had the case for very few days before they sent it to the embassy - I assume this means they also found it to be solid.

I'm going through the P3 for the embassy in Cambodia. #5 is "Evidence of Relationship". Are they asking for the same evidence again? Or are they asking for any evidence that occurred since we filed? I left Cambodia in June. We FaceTime every single day and text throughout the day. We aren't connected on Facebook because I don't use it. I don't send letters or "gifts" because the mail in Cambodia is terribly unreliable and up until just recently, they weren't processing international mail because of Covid. I don't send him money because he works and doesn't want/need it. Are they asking for another letter of intent to marry or do they want screenshots of text messages? What else should include?

I am referencing the K1 flowchart:

In #8, it says that the embassy will send forms and checklist to the beneficiary. Is this still accurate? I posted on here earlier this year asking about changing beneficiary mailing address and was told it doesn't matter because they won't be sending anything to them.

I just moved and I need to change my address. However my petition is already on the way to the embassy. Do I change it with USCIS, the DOS, or both?