That she knows there are things that Giles would consider doing that he would go to Faith first instead of Buffy.

Hmmm. Interesting idea - about Buffy thinking that Giles mostly uses her as a window dressing, like Andrew's recruiting video. Quite possible. But it's hard to judge because we don't know who's the boss.

I think Giles and Buffy are on course for a major blow out where she's going to wonder if it's up to her to stop him.

That could be interesting. And truly heartbreaking.