Make the tab headers (with the file names) occupying not only one line.

[deuse]

Make the tab headers (with the file names) occupying not only one line.
If you have a lot of files open (which nowadays happens very often), you can't use the tab header for changing your active buffer without scrolling the tab header line.
This scrolling is very distracting.
If tab headers would be arranged in several lines, scrolling wouldn't be necessary anymore.

[Tim Kemp]

@deuse, at the right end of the tab bar is a triangle. If you click on it, it gives you a drop down list of all the tabs. I realize this doesn't completely address your request, but if you didn't know about it, it may help you out.

[deuse]

Yeah, I knew this. But that small thing is hard to hit with the mouse, unnecessary and distracts from work.
I think that a comfortable UI, usable with the mouse but also with the keyboard only is the most important feature for an editor.
But thanks for your advice.