The 3-column screen layout (when adding an extra column for a code window in the Tools > Global Options > Pane Layout) is very practical, especially on a large screen.
I suggest that this should be more flexibly configurable by letting the user choose :
- to display the code at the center of the screen (second column) instead of on the left, reducing eye strain
- if columns are split
- which tabs to show in which pane
- or maybe even drag and drop tabs between panes, like in Photoshop.