Nothing shouts "limited resources" as much as a battlefield which is all strenuous foreground action with nothing going on behind. Note to TV producers: if you want to fool the public into believing you've got a movie-sized budget, think in depth. Always have something happening in the background. Fill that empty field. And if you really don't have the extras- or the wrecked waggons or burning hayricks- to pull this off, shoot at close quarters, from above.