Public administration looks to me easy right now though it isnot in your list.but i feel ES And geography are linked besides Mian muhammad shafiq book of general science and ability not only covers Some part of geography but of ES as well....while on the other side in between GS and sociology and Journalism ....sociology said by many is quite scoring and easy i m not sure about GS Journaism and psychology....thats my thinking..least you must choose atleast one to start with..i perceive PA is right option to start prep...and then after its completion any favourable subject related to it would be best to continue....rest is your choice...i would appreciate much better opinion....☺