Need Help!!!

Hi, a little over a year ago i was applying for my green card through the DV lottery. This platform was SUPER helpful and i am glad to say i have been in the US as a GC holder for over 10 months now. THANK YOU to everyone on this platform. I have recommended this to many many people.

I am here again:D. This time because i am about to get married to my girlfriend of a long time. I will like to get some guidance or even a link to information on this platform as to my case if anyone has had something similar.

My background.
I am a GC holder who is a Cameroonian. I meet the salary eligibility requirements. I live in Houston. I am getting married in March 2021 and will like to apply immediately after that. Based on what i have been able to gather from this forum, blogs, USCIS and Youtube, i will need
As petitioner
- Green Card copy
- Tax returns
- Marriage Certificate

Now, we have been dating for 7 years and have lived together for more than a year in the UAE. Pictures are no issues - we have 7 years worth of vacation pictures, etc. Marriage photos will be taken but it will be a small marriage with just 1 or 2 friends as we will just sign at the consulate. I have lease agreements in our name.
My questions
- Are there any more supporting documents you suggest i should get? I have
* Marriage Certificate
* Pictures (Whatsapp chats, Vacation, Wedding, dinners..etc)
* Lease in Abu Dhabi in our names
* Affidavit from my brother in law and a friend
- Are all these supporting documents required at the time of the online petition or Can i go ahead and file and then gather these documents later?(i know the GC and Marriage certificate is needed at the time of application)

Thanks in advance for any input you give me.

- analain