Maths, Bio, Psych, Soc is a good combination. Physics is also a very good A-Level to have, especially if you like it and find it easy. It will give you slightly more options later (e.g. almost all engineering degrees require physics and it's very favourably looked upon for other quantitative degrees). Id' probably do only one of Psychology/Sociology, but you have two traditional subjects either way so it doesn't really matter much.
Maths, Physics, Bio, Psych/Sociology