Help me in final fantasy 12?

help!!!,in final fantasy xii i'm level (31-37) my characters betwwen this levels,i 'm in mission killing dr.cid where is the best place to level up,please or any other advices?i appreciate it i have 2 of my characters with 3 quicknings and others with2 (ashe 3,fran 3) others 2.so please some advice to kill that cid!!!!!