You know who else's acting was really good this episode? Jack Gleeson's. He showed a range of emotions beyond sneering and snivelling, and did a convincing impression of a conflicted, immature but ultimately selfish young man. I was impressed, but goddamn did I want him to die.
I actually wanted Stannis to win, so long as it only dethrones the Lannisters and doesn't take all the other interesting Kings Landing folk out too. Varys, Littlefinger, etc. could stay and serve Stannis, we'd see more of Davos (if alive), Melisandre, etc. while the Lannisters (minus Joffrey) fled through the tunnels to join up with Tywin.
It would bring an interesting dynamic to see a different family in charge in Kings Landing, and I fear that this was the only chance for it to happen!