Hi @Tokki
1. You need to tell the truth as of the time of filing. If you live at different addresses when you file, you need to list different addresses.
2. No, the beneficiary cannot leave the US before getting Advance Parole. If he leaves, he will abandon his AOS application. No, EAD should not affect H1B.
3. No, you should file ASAP after marrying, there's no need to wait. Immigration takes a long time.
4. For affidavit of support, US citizen income information is needed. It's ok if you haven't filed jointly at that time. If you don't make enough to sponsor your spouse, you would need to find a co-sponsor. For bonafide marriage evidence (should be a different question), you may submit marriage certificate, photos from your dating times / proposal / wedding. Any documents related to organizing the wedding (venue reservation), plane tickets with both names, messaging between both of you, receipts for presents etc. During the interview make sure you're you're ready to explain why you didn't live together initially and how you moved together etc.