Do the people vote for ministers in member states? Commissioners are appointed and they are appointed because the governments they appoint them are so horny for power, they want to exactly pick the person they want.
I want Commisiooners that are appointed by a president that is elected by the parliament (that's just how the German government works) or a similar system, but such a system would take too much power away from the governments of the member states (and give too much power to democratically elected EU institutions like the parliament) and as such was, while discussed, always disliked by members like the UK.
The EU is structured the way it is because the (elected) member state governments want to preserve their power and influence. They don't want some other democratically elected EU institution taking away their power. Commissioners are basically member state government surrogates. And this doesn't even yet touch upon the fact that hardly anything in the EU gets done without member states' governments direct involvement, either the Head's or the ministers (all democratically legitimated, by the way).
You are lacking a very basic level of understanding of how the EU works and why it is structured the way it is. Member state governments typically actually have a problem with democratically electing more people in the EU. They would much rather just send someone they appoint or go themselves (for obvious reasons). You are calling for something the UK has always blocked.
Also, you don't seem to know that there is an European Parliament? Democratically elected? Seats assigned proportionally? The last election was in 2014.
Norway: they are not a member of the EU but a part of the common market. That gives them the option to opt out of some things (but not even most things and especially not central ones like freedom of movement of labour), but they still have to pay membership fees and get no say when the rules are decided on.