I just buy the figures I like, which generally are adaptable to many different scenes. I do not worry about whether it is the whole series or whatever since the manufacturer's vision is likely different than my own.
For the collectors who like to put together dioramas. Do you guys (gals?)buy items with a specific diorama in mind or just buy everything you can that comes along and then build a diorama from the items you already have?
Bill W