The other angle to look at it is...
The purpose of immigrant visa is to reunite US citizen with their foreign spouse.
If you already live together elsewhere, you're already reunited, and why should a visa be given? This is why domicile is important.
Living together as a proof is more critical for adjustment of status cases.
You don't want to do the minimum. The more the better. $30-40K+ is much more likely to get accepted. And $100K+ is for sure accepted.
I'm not an immigration lawyer, but to me claiming FEIE highlights you're living abroad and working abroad, undermining your claim to have US domicile.
Yes, this is correct for I-485 form.
Check the box to issue card, this will save you trip to SSA.
If I-765 approved, restricted card will be sent.
Then when I-485 is approved, unrestricted card will be sent.