I don't understand the democracy argument when our own system is no better. The House of Lords is filled with hundreds of unelected people that can dump any legislation they don't like. And it's not like we get to vote for which politicians end up in the most influential cabinet positions (I sure as hell wouldn't vote for Hunt or Gove to run anything).
With the EU we vote for our MEPs who represent about 10% of MEPs so we have good overall representation. The EU commission that propose laws are made up of 28 representatives and each one is determined by the leader of each country. It's not different to any other civil servant. They can't actually pass any laws without the agreement of the MEPs (who, as I said, we vote for).
That's a complete non-sequitur. 80% democracy is better that 60%. It's not binary. After we ditch the EU, we can consider ditching the house of lords if we want.
Yes, the commission proposes the laws. That's where the power lies. The MEPs input into that is incredibly weak, because you slant everything by only ever proposing laws that go in a single direction on a particular issue. Imagine if there's an issue where the population is divided between positions A and B. Half of the MEPs are therefore representing people who want position A and half for people who want position B. Well the commission can then propose 10 different laws that work towards position A and none than works toward position B. They'll then say "well you had the chance to reject our 10 laws, so it was still ultimately up to you". That just doesn't work. Sooner or later, that leads to you going with position A. It's just rigging the system. Like weighting a coin flip.