The Rose and alt!Pete relationship is getting some really interesting discussion in this
this thread so I'm going to talk about the Doctor/Rose (surprised?) relationship development instead. XD
-Much as Girl in the Fireplace frustrates me, RoC/AoS compliments it well. In GitF, we see Rose supporting the Doctor through the whole Reinette thing. In the Cybermen episodes, the Doctor takes on the role of emotional support as Rose struggles with alt!Pete and Jackie. Much as I like their honeymoon phase at the beginning of the season, the middle of S2 is about them grappling with outside emotional issues... and finding that they can still rely on each other. It veers nicely into the deeper, more intense bond that they seem to have for the later half of S2.
I love that moment at the end when he seems to intuitively know that what she needs is a hug from her mum. Aww.
-It's really interesting to me to the see the Doctor getting so wrapped up in someone's domestic problems. (And a nice development from Nine's season who tried so hard to avoid getting involved in Tyler domestics).
This moment is so cute. He goes from Happy Babble to Concerned Face as soon as he sees Rose is upset. How often does the Doctor clue in enough to tell from the look on someone's face that there's something wrong? XD I'm not saying he does the role of "emotional support" very well (there is a lot of arm waving and yelling in this two-parter) but it's cute that he's trying.
-I also love the way the Doctor spends most of the first part trailing along after Rose. I know some fans think that Rose grew more passive in S2 and became almost a sort of a Ten fangirl, but I think it says a lot that she's the one determinedly going after her dad (despite the Doctor's protests), and the Doctor.... has no choice but to chase along after her. XD Actually, given this two-parter and his "I believe in her" speech in The Satan Pit, I would almost say that it's the Doctor who is a Rose fanboy. :p
-And then there is this scene:
Cutest thing ever, y/y?