You're treading on ground where many, many have gone before - but it's always an interesting topic for both thought experiments and statistical evidence.

I agree that there are some issues where lack of knowledge has a detrimental effect on public policy (e.g. protectionism, which correlates with dumbness more than it does liberalism or conservatism) but there are far more issues, typically more important to the average person, that don't require you to know that the Sun goes around the Earth (e.g. abortion, punishment vs. rehabilitation of criminals, level of taxation).

My feeling is that whenever you restrict power to a group, the group will vote to further increase its power, with any economic benefits being secondary, and likely negative. Also, dehumanizing one group of people, while deep-set in human nature, is a dangerous thing to start doing, which history illustrates repeatedly, and which other people have picked up on here.

More importantly - you talk about decreasing the voter base, but as your examples illustrate, the problem isn't really with the marginal dumb voter. The problem is with people that know some things, but not enough things - like people that think they're smarter than they actually are. As things are now, even if there weren't destabilizing effects from this new voting system, you'd essentially have to restrict voting to a very tiny base to get the results that you'd like.

But if I can try to help us find some common ground - instead of taking the vote away from people, let's allow free financing of campaigns, so that the most economical solutions will be touted strongest.