Haven't seen The Doctor's Daughter, so allow me to nitpick a something in The Sontaran Stratagem.
When the two Unit soldiers find the clone tank and then encounter the general, one of them mocks him for being short. The general replies, disappointedly, that "Words are the weapon of women." Why would it do this? The Sontarans are clones, they have no sexes and, one would presume, no sexism. It would make sense for a race or tribe where only men were warriors and the women were kept in other, less esteemed roles (such as feudal Japan) but makes no sense here.