^actually they did fight before Becoming pt2. The one when Buffy got hospitalized. Angelus got the upper hand and I really thought he would bite Buffy in the neck but then Xander came
I just wish the writers was able to delve deeper on Angelus' feelings for Buffy. They kinda left us hanging on his famous line of "To Kill this girl, you have To Love her"..but then, if he really wanted to kill Buffy, why he didn't continue to pretend as Angel so he could play her emotions further more? He killed people to get her attention, provoking her to be
angry than stay in-love him....
..It would be interesting to see how Angelus was conflicted on his feelings for Buffy. He is an evil vamp with so much pride! He always wanted to be in control that's why he killed his father to make him feel he was over him. He might be Darla's boytoy, but then we knew eventually how Darla could be able to leave him once in awhile and he would join other vamps (such as Penn) to create havoc in other place. He is SO confident of himself, that's probably why when he felt "something" for Buffy, he suddenly lost control. For Angelus, human emotions such as Love, is an act of weakness. So instead of looking weak, he just want to seize control again by destroying the world. At least, that made sense to me
Angelus/Buffy has SO MUCH potential storyline than the one we got during S6! If only the writers had found a way.....BTVS might have ended with much MORE INTEGRITY than it had.