Season 8 has (episode "The Caretaker") with Peter Capaldi not only a phenomenal actor, but also the quality of the scripts is much better again.
In Season 6 and 7 made quite frequently especially the resolution of the plot not a good figure, what actually exciting concepts (eg, "Journey to the Centre of the TARDIS") was completely drive through a bad end before the wall.
At least so far seems that matter to be re-entered improvement, because only "Robot of Sherwood" left to be desired as far as the end desired.
