You got a great amount of enthusiasm,but I think you should also think what you`d do if your pilot aspirations don`t go according to plan.Have a backup plan / backup skill ready just in case.
For example, I`d suggest Geography / Meteorology or Electronics.
The Maths and Physics should be enough,once you`ve done them,you can do the ATPL theory through a distance learning course..as for uni, I`ve heard of courses in aviation engineering but nothing more than that really.