4. There's No Need for Story Arcs
One of the major changes between classic Who and new Who is the story arcs that run throughout each series. This is also due to the current television landscape. Since Doctor Who originally went off the air in 1989, story arcs have become more and more common in televised dramas. Thats not to say the classic run didnt have its share of story arcs as well. There was the hunt for the Key to Time that took up all of Season 16 and the Trial of a Time Lord arc that was the basis for Season 23. But the new series has placed a heavier emphasis on arcs than fans had anticipated. Some detractors say that these overarching storylines get in the way of what Doctor Who is supposed to be about. Namely, an alien time traveler having different adventures from week to week. I dont see it that way. I see these story arcs as a means of developing the characters and challenging them in ways that the classic series was unable or unwilling to do. Admittedly, the arcs have played a much larger role under Steven Moffat, particularly in Series 6. But Series 7 has been relatively arc-free thus far, even to the point of not having any two-part episodes. I think it helps to have diversity in storytelling and Doctor Who is certainly no exception.