I will make a more general point rather than an EU one.
In my view democracy is in an absolute crisis globally driven by short term thinking, a medi dominated in countries by wealthy businessmen with very specific self interested agenda and a 24 hour news cycle based on sound bites. Few politicians anymore (this is aimed at both sides) have any interest in long term politics , they are interested in keeping their position in power in their party through polls and then winning the next election. As such democracy is increasingly selling out countries futures for infividuals short term individual goals.
For politicians Decisions have therefore become populist, the truth doesn't matter , people have moved on to the next story already, winning today's news focuses them and most politicians are happy to keep going down the river as long as the waterfall is only reached after they have moved on.
Bureaucrats on the other hands are paid to be in their job, they don't need to make "popular" decisions to stay there, they don't need to appeal to the lowest common denominator and they don't need to make short term self interested decisions. If they want to make the right call they can.
It is why so many of the economic powerhouses, countries with the best infrastructure, etc have often been far from the most democratic. They could be genuine democracies but with a history of stable government but they have long term plans. On the other hand those that change the most, are the most political and the most populist are the ones that fail.
add to that the fact appointees can be experts in what they do, they can have properly researched it.
Letting elected politicians run economies and make cases on law would be a bit like letting them become generals in the army, letting Jeremy hunt start being a surgeon.
I am not saying democracy is wrong but putting all eggs in one basket is a real risk. Brit's in currently has checks to too much short term idiocy from our politicians provided by Europe due to the scandalous absence of an effective second chamber or other branches of government without it a prime minister and their government elected by in Cameron's case 1 in 6 of the population could run amock.
So in many ways I am far more comfortable with experts with no real vested interests driving the specifics of laws, the economy etc with the politicians setting the long term strategic goals and plans to drive the country where the people want to go, which is unfortunately very far away from what we have today.
Te other thing with democracy is this whole concept on national interest which kings invented to serve the interests of their whole wealth and power that we all fell for.
What Britain has is the individual interest of 60+ million people and national interest does not exist. The rich across Europe (indeed the world) share a common interest, the unemployed share a common interest, the young or old share a common interest and these interests are far more fundamental than the interests I have being born British or living in the UK.
But like religion , nationalism has created a tool to control the people, a strong emotive tool that allows them to be controlled.