Help needed for FLR spouse visa extension application.

Hello, I am due to apply for my wifes flr spouse visa extension so i have a lot of questions and to the moderators and people who reply to this forum i thank you for all your help. I will not be seeking legal assistance as they are asking for amounts i cannot afford. Hence, seeking advice here.

Situation:
My wifes spouse visa application was approved and she has permission to be in the
UK as PARTNER (Standard) from 11 Jan 2024 until 11 Oct 2026. She officially arrived in the UK on the 27th Feb 2024. We are a young couple and we had a daughter on october 13th 2024 who is a british citizen aswell as me. She will be 23 months old at time of application.

Question 1.
We will be looking to apply for FLR between Sept 13 - Sept 18 2026. Is that fine?

In terms of financial requirement, we applied meeting the old requirement of £18,600. I work for a leading major uk airline and still present there and its coming to more than 3 years now.

Question 2.
Do i still need to meet the old requirement of £18,600?

Question 3.
At time of application, can the bank statement i provide to show my 6 month payslips be simply downloaded from my bank nationwide site or do they need to be signed or stamped by the bank,
So can they just be digital pdfs downloaded from the banks website?

Question 4.
This is in relation to the employers letter, at time of spouse visa entry application, my manager gave me a letter which was perfect but i now have a new manager who recommended me to use the letter provided by companys computer generated system which confirms my employment. It states my name, badge number, address, companys address, has airline logo on top, confirms my base pay, bonus amount, states my employment as permanent, date of joining, tax reference, national insurance number, signed and dated by the payroll operations manager. Is this ok? It does not confirm my job role, how long i have been paid my current salary and that the payslips are genuine. This raises serious issues in my mind.

In terms of accommodation, we are a young couple and we live with my parents in a 4 bedroom house which is a council house and rented to my mother. My mother receives housing benefit. I have other 2 brothers who live at the address too aswell as my parents.
At time of spouse visa entry application we showed the same property and circumstances.
Docs we provided was no objection letter from my mother signed and dated with passport scan, housing inspection letter from council confirming the property is not crowded, tenancy agreement, one month utility bill, council bill and a letter from the landlord FORHOUSING company.

Question 5:
We now have a daughter so does this make the property overcrowded and would it make an issue? Its 4 bed with mom and dad in 1 bed, me and my wife and our daughter in 1bed, and my other 2 brothers have 1 bedroom each.

Question 6:
Do i need to get another housing inspection report/letter from the council again? It costs £150. I would like to avoid it if i can and it does not weaken our application.

Question 7:
I receive child benefit for my daughter under my name only. This means my wife has not breached the no public funds requirement right? And do i need to provide proof of this? That its only in my name?

Question 8:
My mom receives housing benefit. She has confirmed to me that it never increased due to my wife or daughter living at the property and that the only increase that happened was the normal increase which happens yearly due to government increasing it which is normal. Is that correct and do i need to confirm with government or provide proof of this?

In terms of proof of relationship, we will provide our marriage certificate, my daughters birth certificate and uk passport, aswell as up to 5 photos of us together. Is that sufficient or do need to provide anything else?

In terms of proof of cohabitation, we dont have much letters that come to this address as we live with my parents.

Question 9:
How many letters or proof do i need to provide to meet the Proof of Cohibitation requirement per person?

Question 10:
Most of our proof of cohibitation are digital letters which are pdfs that have been emailed to me such as, digitally downloaded from bank website bank statement, aviva pension annual statement letters, three phone bill. Are these digital online letters ok ?

Question 11:
Is there any requirement or letter that i am missing that you would reccomment? If there is something that i am missing in this application please let me know.

Thank you for taking this time out to reading this. Appreciate everyone that is going to help me.

Can anyone help me with any of these questions please?