[South]

I also think in return to RTD's previous Doctor Who stint, we may have already seen the seeds sowed for the next series finale being planted during these three episodes. If I recall The Meep mentioned something about "telling their boss" (or words to that effect). The Toymaker also made a reference to someone who he didn't play a game with, I think due to being scared by.

Having watched the episode I was left feeling a little short changed, yes it was good, but as others have said considering the toymaker was trailed as the big bad, I would have liked his downfall to be something riskier essentially he lost in a game of catch.

As far as the theory regarding the set up for the next series I think that is true with the big boss, it's clearly that is going to be a new bad wolf moment.
But in addition I am also wondering if the arc is going to cover the entirety of Ncuti's tenure ala Marvel with story arcs over multiple stories, series and films. It would not suprise me if the 14th and 15th doctor feature in the 15th doctors final episode.