Yeah like everyone said above I reckon keep with advanced, your scores are good anyway for advanced. Also with advanced you can pretty much just learn the methods for questions and then you'll be sweet.
Also I would recommend keeping business over modern, probably just because I prefer it (I do both), and business you can just sort of learn the syllabus and you'll be sweet whereas modern there is a very broad range of stuff you can learn but that's just personal preference. I think if you're interested in the subject you'll be inclined to do more work so ultimately do the one you're more interested in.