Play through Story mode and take every boss' picture and any gang members desired, but make sure to leave at least one. After completing Story mode, take any remaining pictures you have not taken to get around 15 Hero Points. Then, save the game and reset your Wii. Load your saved game file and you should hear and see the Villain Photos complete and get another 15 Hero Points. Spend them, save, and repeat the process as many times as desired.