Saying "Xth should have done Y because Zth would have done so" is really a poor argument... Even though they share the same memories it has often been made a point that every Doctor is unique and what one would have done is completely irrelevant to what another does.

10 trying to save Davros was him being... how to put it... him still being the repenter, the pacifist, the person who would love to save everyone in the universe because he is Space Jesus. Not always, but that was 10's stick most of the time. 11 is not that person. 11 is not trying to save all of space time. He was willing to take quite drastic measures against the Silent. He fought a war at Demon's Run.
Admittedly, yes I would have liked Oswin to be saved but I guess there was no for one no time (maybe) and on the other hand as Nikita said, she was apparently fighting a losing battle against her reprogramming. He wasn't cruel there but I guess they could have made a better point of explaining why he didn't save her.
As for Filch... he was a bastard and he deserved what he got. It was not a good thing to do what 11 did, but it wasn't some horrible crime. It was just 11 being what he was tending towards for most of his characterization.