Well Adam. You have a lot to learn - for instance JMC are currently sponsoring cadets through a scheme run by the CTC Academy, Britannia recently type rated a host of low time pilots and MyTravel this year accepted in a load of ex-cadets they had trained prior to Sept11th. So keep up your PPruNe'ing to keep properly abreast of events.
On the matter of the ATC. I think its the single most proactive thing someone of your age can do towards a flying career.
The ATC provided me with my license and my first flying instructional qualification. I could pass the PPL theory exams at the age of fifeteen based on ATC lectures and study alone. The experiences and opportunties provided within the organisation will stand you in good stead at any future interview.
Its a no brainer really. Join - then make an effort to attend every event, have a positive attitude and most importantly - polish those shoes 'til they gleam.
Good luck,
WWW