: As a result, I may decide to split the Marines into a few
: locations; half at the end of the stream, for instance, and then maybe
: half on the cliffside hilltop. Then I'll have an excellent save that's not
: too easy and gives me options.

Actually I'd advise against splitting them, because a Banshee could easily get distracted by the group you're not with, whereas you want them both to focus on your location. There's an example of a Banshee getting distracted by hilltop Marines in BCM66 (Banshee assisted Warthog stunting), in the 'Spin' clip at 2:29.