If you go and ask most Europeans about how they are represented in the EU.....the general answer is by representation and some election. Don't ask them when the last election occurred, because most have no idea.
So, here is how the mechanism works. There is an election every five years throughout the 28 member states, and each country is allotted X number of positions, which are all filled proportionally. From all of the states, there are 751 seats up for grabs. For the state of Malta, that means 6 seats. For the state of Germany, there are 96 seats. If a country's population goes down, their statistical average changes and they could get lesser seats. Or for another example, if you had an aggressive pattern of immigration (say 750,000) where they were coming in for five years, then you'd likely get MORE seats.
You, the voter, don't vote for one single person. You are voting for a party, which will detail the representation job to one of their party members. In Germany's case, there were only 5 CSU members given seats in the last election (2014). The general five-percent rule (used in 16 German states and the federal gov't)....doesn't apply. So, you also will note that the Pirate Party (with very limited votes) got itself one single representative onto the 96 German member listing. One NPD (Nazi-Party) got onto the listing as well. Roughly ten-percent of the seats allocated to Germany....end up with lesser-known parties.
Country by country, they voted. If you were counting up right-leaning parties (like the CDU or CSU), then the total is about 24-percent of the 751 seats. The Linke Party group (the Communist crowd) got around 6-percent of the 751 seats.
You can go and ask 99-percent of Germans to name a single member of their 96 seats, and the only name that will come up is Martin Schultz, a SPD member, and who plays a key leadership role in how the EU functions. You might notice him once or twice a week.....featured in some German news episode or giving a ten-minute chat on such-and-such issue. Beyond that....99-percent of German society has no real idea who sits for them in Brussels on the other 95 seats.
Could the party apparatus send some idiot to Brussels? Yes. Could you say anything about this? Well....you get one vote every five years (the next one coming in the spring of 2019).
In 2014, roughly 48-percent of German society came out to vote in the EU election. So, less than fifty-percent came to vote. The peak, if you were interested....was 1979....with around 66-percent of the public showing up.
State-run TV will carry a number of hours of discussion prior to the EU election day, and give all parties a chance to display their charm and character. They usually talk about their accomplishments and all the good that the EU accomplishes. There aren't any real attempts for private advertising, although you might see some newspaper carry a piece in a certain way.....to benefit this party in the positive.
In case you were curious, Malta had almost 75-percent of it's population show up and vote in the same election. So country by country.....it's a different story and different appeal.
It's all democratic in nature, and the rules are absolutely written down and known by everyone.
Could you improve this? If you had more frequent elections, I doubt if it'd really matter. If the general public could drill down into stupid behavior and identify one particular party to vote against in an EU election.....there might be more happiness among the public. But frankly, no one knows much of anything over this whole apparatus. And the EU folks? I think they are happy that the media and public doesn't bother them in Brussels.