cory's potted guide to the appeals process
From my own experience of the appeals process it will not make any difference how many or how few other parents go through the appeals process. When we appealed, there were 35 other parents appealing on same day for same secondary. We still got a place (though we may well have been the only ones).
Once the places have been allocated, the school's position is that they are full and they do not want to take anyone else, thank you very much. So they are not going to take even one more pupil unless they have a really strong case. Normally either that the LEA have failed to follow their own admissions criteria or that there are very special compassionate grounds.
In the appeals hearing the LEA/school will argue that your child cannot be admitted without detriment to the school; you will need to argue that the detriment to your child from not getting a place will be greater than that to the school if they have to exceed their numbers. Unless the LEA have made a mistake about your child's admission, this will probably have to involve an argument about your child's special circumstances that would not apply to the hundreds of other children who might also prefer to attend this school. Any argument should be backed up by evidence.
So if you are going to argue that he needs to be with his friends, it might be an idea to include a psychiatrist's report to explain why he is extra fragile (after all, not unusual for friends to go in separate directions at this age). If you want to use the transport argument, again a letter from a doctor explaining any special reasons why he cannot use the normal transport arrangements (most secondary school children make their own way to school by foot or on public transport unless the school is very far away in which case the LEA will provide transport). Though tbh the LEA might well decide to provide transport for a special reason rather than allocate a school place.
In any case, the appeal has to be about the needs of your child, not about your convenience.
Whatever you do, do not mention in the appeals hearing that you can't accept the allocated place because it's an awful school:
a)this is not the way to make friends and influence people
b)it is also no reason why your child should get a place rather than any one of hundreds of other children
We went through this two years ago as our disabled dd had been allocated a place at a school without wheelchair access. It was well worth it but a very stressful experience and even with a case as strong as that, I really felt I had to keep my wits about me.