from my point of view, acst201 is easier than accg253, at least its failure rate is alot lower - accg unit failure rate is always quite high.
since you've mentioned that u are more of a maths person, then you should enjoy acst201 alot more, it has almost 100% calculation. A good way to preview the unit is going to e-reserve, and check the final past papers of acst201, should give you some good ideas on wat is it about.
but i'd like to remind you, accg253 is a core unit for both applied finance and accounting. maybe u will need to do it eventually if you choose the finance or accounting path.
ps. accg253 and acst201 is a bit related, so maybe doing acst201 can help you do better in 253 later on - i recommend you to do acst201 ahead of 253, or at least at the same time