I would recommend taking a language if possible, as often non-European language degrees, while not requiring you to have studied the target language before, will prefer to see you have some evidence of language learning ability - such as an A-level in any language.
Also if you struggle with memorising things, do think carefully about the prospect of studying a language - invariably there is going to be a degree of rote learning and memorization for the early stages of any language. This is perhaps particularly true for non-European languages where there aren't as many cognates to fall back on and which require you to learn a new script (such as Chinese).
A-level Maths is of no particular use for studying Chinese or politics (there is some stats involved in politics but A-level Maths is far more background than you need for that) so don't take it unless you particularly enjoy it.