To add something to what I said earlier. The reconfiguration system was probably one of the coolest things they've shown, we actually saw the essence of what made the TARDIS so cool. And the moment was dampened by two brothers who were completely unimpressed by it. There should have been something in the scene for us to enjoy the moment more.
I felt somewhat similar about the monsters. When Clara was finding herself into the most interesting places inside the TARDIS, you had to be occupied with a monster chasing her, without as much as an idea on its disposition. I think it would have been a little bit better if they did not seem bound on chasing and harming Clara, and instead were more benign and just making her nervous. But maybe that's just me.