You could take AH bio and chem, plus another AH, but you could probably get away with taking one or the other and then two other AH (if that makes sense).
Other than bio and chem, I'd recommend maths or physics if you enjoyed them at Higher.
'Easier' (which is down to personal skill set) AH's are English and Business Management. I'd take AH's that you have Higher's in, but you could be okay with just two.