Hi, might be a bit late, but thought I'd throw this in! I did A Level History, Ancient History, and Sociology (I did English Lang&Lit at AS). Your topics will be really good together, because they're all essay topics - it means more work, but it will really help you in honing your essay skills. The thing I found with doing these topics is that they all intertwine with topics as well, like you can find something in Sociology and think, "oh, so that's why they did that in the past." (that sounded better in my head). This will likely be the same with Psychology, because you get to really understand the actions of Historical figures.