The current view system uses tabs. I consider tabs inside tabs as a bad GUI design.

IMHO it would be a waste of effort to expect each application to provide its own dark theme. This is the task of the operating system. We helped those users which have their operating system set up with a dark theme by providing a dark editor color theme.

BTW, I've tried to implement a dark theme with SWT, but it looked horrible because a lot of colors, e.g. the selection colors, are NOT configurable. Maybe this situation improves in the (mid to far) feature.

What I don't fully understand is why you want to open the 3 files in your IDE. Just to find the files easier where you were working on the task and now have to continue, or to undo some irrelevant changes? What if you deleted a few files in your branch - should they also be shown for editing (or just those available in the working copy)? Do you need to see the changes made in your branch or just the files (that were changed in your branch) in its current working tree state?

In your opinion what should be searched for - file names (of open repositories), repository names/paths, branches, tags, commit IDs (could be a long list when just having typed 1 char)?