I became a massive fan of Who about a year and a half ago and decided that I wanted to become extremely familiar with the show as a whole in addition to the recent series. So far it's been fascinating for me to see how the Doctor, for example, doesn't know about the Daleks initially and that the Thal were the ones who used to be the warriors on the Dead Planet.
This makes me wonder about the Dalek's original standpoint on violence and the like. They had to have been pacifists until provoked by the Thal, meaning that the Daleks were forced to become hateful and devoid of feeling in order to preserve their race. It would be interesting to see the Doctor travel to the time before the Daleks became cold-hearted octopus-like creatures in machines.