I'm really into science, so I'm going with Chemistry and Physics.
I heard 3 Unit Maths and Physics go well together. But I'm probably going to drop down to Advanced Maths, I just need to see how it goes (looking at how assessments go).
I'm in Advanced English now, and I find that I'm do alright, so I'm choosing English Advanced.
I go to a Catholic School, so I'm going to take Studies of Religion I.
So I have an extra unit left, and I think, after reading all the helpful replies, that I'm going to do Economics, and this means I'll have an extra unit, but it should be fine.
These aren't down pat yet. I need to see how I go in assessments, and what other subjects have to offer. (I realise that it's extremely early, but holidays are a good time for thinking about these things)
Again, thank you for all the responses! It's really helped me.