FicWad: fresh-picked original and fan fiction

I like the idea of the story. However, some of the plot points you've mentioned are a little dodgy, a few chappies ago you mentioned that only in Europe were there dark lords... That concept is colouring your story in a negative way, humans all over the world have always had the potential for great evil. From Hitler to Mao to the current GW Bush, in the name of power and control all humans are capable of evil. So too would all wizards, after all neither they nor we are gods (and if you've read the entire bible, god too has done some pretty evil stuff.) Although a meritocracy has been a better way of doing things than the traditional corrupt forms of govenrment, it also allows the most competent evil person to rise into positions of power as well as the good people...
The main flaw in your plot is the number of people hp is murdering, there is a big diff between someone who kills in defence of self, or others, and someone who plots and brings about the death of another. Yes, even if it can be said that that individual deserves to die. The story you're writing is a fictionalized account of a revolution, the sweeping away of an old order to bring about a new one. To improve your story you'll have to explain how this hp is going to avoid the excesses of what happened when the muggle gov't's/societies did the same; Examples given, the Russian Revolution (which pooched the economy of the ussr, and killed at least 50 million people in the name of comunism), The French Revolution (which also pooched the world economy, killed who knows how many people, and collapsed into a state of perpetual war).
If your harry succeeds in overthrowing the govt and offing this voldy early how is he going to prevent anarchy in magical europe? Should your answer be that democracy will solve all of their woes, I will have to remind you that the democracy brought to Iraq (at the point of a gun, really just colonialism reborn...) has killed and tortured more people in less time than Saddam could have. As far as the success of the US revolution goes... Explain again how is it that GW bush can claim to be an elected president???