I cast my vote for Ctrl+Tab as an � at least � additional shortcut. Ctrl+F6 is everything else but comfortable. You either need a big hand � even then you have to use your thumb instead of the fingers available in the natural typing position � or you have to use both hands.
Edit: By the way, some related enhancements:
Ctrl+W should close a tab (no confirmation).
Ctrl+Shift+W should close all tabs (after confirmation).
Ctrl+T should open a new tab.
All these shortcuts are accessible with the left hand only and are standard in many tab-equipped applications.
Thanks for a very nice editor, it has been featured yesterday in one of Germany's finest freeware boards:
http://essential-freebies.de/board/viewtopic.php?t=12452Icfu