As I am working through a scene, and contemplating this question on my own, I thought it wise to tap into the experiential resource that is SocialSoundDesign.... Let's get your insight!
The sound: Ambient "battlefield panic" to accompany several (and I mean SEVERAL) scenes throughout an American Civil War documentary. Cannon shots, men screaming, horses, more cannon shots....the works!
The situation: The most distinct sound in this scape is, of course, the cannon and gunshots. I have a limited selection of raw samples of each to work with. ...and no, I am not in a position to create any more of my own. That opportunity has passed.
Do I, A) use only a few of the best sounds MANY, MANY times each (going loony with Pitch, and TCE to change it up), or B) do I use a variety of my available samples regardless of tone, perspective, and timbre?
I'm leaning toward a mixture of the two options, emphasis on option A. The real question here may be: Which will an audience notice less - repeated fx, or mismatched timbre?