Family Visitor - Question about Other Close Family members

I'm doing an application for my Brother for Tourist Family visitor visa and have mentioned on the form that he is visiting his 2 sisters and 1 brother.

But there is another question as 8.11:-
8.11 Please provide the following details of all other close family members in the UK:

Which when I read the guidance notes it state the below (see definition of a family member). The bit I am unsure of is that I have a few (about 8 people) cousin brothers and sisters in the UK (Sons and daughters of my Uncles).

1. Do they also need to be entered on the form
2. Do I need to ask each of these people for their permission before writing their name and details on the form?
3. Does having too many people in the UK make the application any negative?

Definition of a family member
A “member of the applicant’s familyâ€

1. Do they also need to be entered on the form

IMO, you can enter as much names as you can, as long as they fit the definitions of family ''members''

2. Do I need to ask each of these people for their permission before writing their name and details on the form?

You dont have to as it doesn't make any difference.

3. Does having too many people in the UK make the application any negative?

I dont think so but remember the applicant must satisfy the ECO that S/he would return home after the visit.