There's a lot of unis that offer joint courses with business which you may want to consider looking into given your broad interests.
Maths is always a safe bet at A-Level, many courses require it and it is always on the preferred subject list for top universities, its definitely necessary for finance and recommended for business
The sciences are also good picks, Physics pairs particularly well with Maths, but Biology might be a better choice if you end up wanting to pursue psychology (most unis don't actually ask for psychology at A-Level)
If you're looking towards something more creative, Art should definitely be on your list
It might be worth picking 4 subjects at the start, seeing which you enjoy the most then dropping/switching subjects a few weeks in