Just my two cents, but you can't go wrong with the Tatooine wave or anything with clones in it.
There's a new "army builder" wave (contains three different clones, battle droids and a new black droid) coming out soon that is sure to do well for you. Check out entertainmentearth.com for more details on the case breakdown(s).Star Wars Cases
Is ROTS popular where you live? If so, the new "Greatest Hits" assortments might work then. Each figure features his/her own cardback that is scene specific - they look really neat. Some loose collectors here in the States are even buyiing them because of the packaging!