Ok. Sorry for being non-constructive.

Perhaps the OP question is best framed as "how does the political/government situation change as a result of ems, and what could be done in the domain of government to ensure effective and valuable government", then go a bit more cautiously into "here's some things that people like about democracy" and "here are some other proposals (like em-dictator modified to be non-power grabbing, em dictator unaware of ability to grab power, etc)"

Many (good) things become possible when you can sandbox, copy, and so on that were inconceivable when the problem was how to get wealthy landowners to agree to pay taxes...

I tend to favor the AI-singleton as fast as possible solution to sidestep these issues, but I'll try to actually think about it as well.