I would say...
- Going to Uni and getting a degree is more about a fall back plan, it also gives you time to develop your personality and life skills. But there is nothing to show a degree helps get the job.
- Doing you A-Levels is great, most the airline sponsored schemes ask for them, and doing your A-Levels will help with some of the selection tests.
I think the most important thing to do is to get a Medical. Dont spend ages getting your hopes up, when you cant pass the medical, its wastes time, money and you end up wanting to be a pilot more as you cant be one.
No flying experience is no problems, some schools like this as you start from fresh there way.
You also need a great deal of cash for a majority of schemes, some help you get a loan, but most are secured, and the ones that arn't require a fail deal of personal contribution. Some schemes dont include food, a place to stay, exams and retake fees.