It's cheaper to get stuff like chess/tictactoe sets, impulse sets, and battlepacks to get mass minifigs. But on the other hand, the more expensive sets have unique minifigs, and trying to get multiples of those will be costly and difficult (especially after the sets go out of production). Just having one of a minfig seems unfufilling for some reason.
EDIT: It's too late now, but I didn't mean like in absolutes. Since I am a castle fan going to use it as an example. Quantity would be mostly regular soldier crownies with a 0-1 of the kings, golden knights, grey knights, queens, villagers, etc. Diversity would be a couple of more of those unique minifigs and less of the cheaper regular minfigs.
Like for star wars, is 2 senate commandos enough? or would you want more, etc.
Edited by lego40k, 07 October 2009 - 01:18 AM.