It's because the game was just so gosh darn great

Okay... I'll PM you the 'cons'.
Cambridge does have a few different subjects, but generally that's only because it's offered around the world. For instance they offer Hindi (2nd Language) and Child Development to name a few. Our school doesn't actually let us do them though

The other differences are that some subjects are broken up into smaller subjects whereas others are combined. English is Literature and Language where as Calc and Stats all come under plain old Mathematics. Unfortunately we're only offered the option of doing four subjects at 6th and 7th form level so that limits our options by a fair bit.
Right now I'm not doing any hacking due to exams but I am will continue to hack afterwards. I'll probably release a beta of Frontier soonish, a game which just showcases some skills as it really is just an edit of FR. For DNA I'll be releasing a beta with a fair bit of gameplay in it soonish as well. Orange won't have any releases for a while however. Anyway, off to bed for me, exam tommorow.