Taken to the extreme, you could have a direct democracy where individuals vote directly for proposed bills, bypassing the (usually vested) middleman. Voters would have to pass some competency exam on the subject of the bill before being allowed to cast a vote. In other words, you can't vote on internet regulation if you don't know how to access a web page.
The reason there will never be a license to vote is because you transfer an immense about of power to those who create the exams. Influence the exams and you decide the election. In addition, by putting up barriers towards voting, you decrease overall participation in the election, possibly alienating the general population.
Perhaps a better, more realistic option is to move towards direct democracy while simultaneously improving as much as possible education.