Hey there Danny,
I'm currently going throught the second year of A Levels and take it from me, dont do a subject like Maths or Physics because the application form for BA told you so.... 6th form life is good, but if you're in a subject you dont enjoy, then its twice as hard and you're most likely to do badly in it, and that wont look good on your CV.
I asked this question over a year and a half ago and was told this:
Do the subjects you are good at and the ones that you enjoy, this will put you on a good path for the airline job that I take it you want (?) because you'll have good grades behind you.
For example, the Leeds uni course that I wish to embark on preffers me to have an A Level in Physics. I do English language, Geography and D&T but this isn't a problem as long as I show a MAJOR interest in getting that airline job.
You say you're thinking of doing English Language, I've really enjoyed this course even though its quite tough. It also gives you an advantage on the "people person" side of being an airline pilot I should imagine.
But sure, if you're good at physics and maths etc. and they will provide a good fallback in an area of work you'll enjoy if you fail to get the airline job, then go for them.
Good luck with whatever you choose and remember that end of termin the 6th form means 'go to the pub'
Ian