But the problem is that Antilogic's system only works if the dictators are incorruptible. All of them. Just look what Nero did! Once you start a dictatorship, you leave it open to exploitation by future dictators.
The republic was an excellent government. No leader, all posts were redundant. I really think that, barring an ability to genetically engineer a perfect line of dictators, we should attempt to emulate the Roman Republic. Maybe with a few more guaranteed rights, and less slavery, but conceptually, it is one of the best governmental systems I've heard of.
I freely admit that enlightened despotism is overly utopian. However, Plato's
Republic, where he argues that the rulers should be wise and educated and thus be based in rational thought is perfectly applicable. I'm an advocate of a more limited representative government, where you have to have some kind of education before you are allowed to vote. For example, a good first step would be requiring a high school diploma in the US before you can vote.
If stupid people can't vote stupid people into office, it's a step in the right direction.
On the politics of the 19th century, the Democratic party was more conservative and split over the issue of slavery: southern Democrats wanted to keep and proliferate slavery, and northern Democrats had a few people who just wanted to contain it, a few who wanted to spread it, and some abolitionists. They ended up nominating two or three candidates for the presidency against Lincoln, and the split vote allowed Lincoln to get into office. The Republicans were the more liberal party and at the forefront of the Free Soil movement, which explicitly wanted to outlaw slavery in new territories (becoming states), and eventually had the goal of eliminating slavery entirely.
This trend switched around after the Democrats absorbed the Populists and all the liberal Republicans left the party with T. Roosevelt to form the Bull Moose party, another group that was largely absorbed by the Democrats. Left was the business elite and Taft, which is where the party gets its conservative basis today.
Now, on the leaders (and on topic):
I'm against Cleopatra for the Egyptians...assuming you are referring to the all-to-popular Cleopatra VII, the Ptolemy who managed to oversee the downfall of Egypt to a Roman province, she is a pretty bad choice overall. Ramses II and Hatshepsut are both good choices, although an early pharaoh like Menes/Narmer (I forget which is the preferred name now) or one of the other good builders listed would be a good call.
And I agree with cybrxkhan on the WW2 leaders: roughly 10% from a time period of not more than 20 years is way too much for a game covering 6 millenia.