Any chance that someone (you/me) adds these features:
See my extension qwin how that works
https://code.google.com/p/qwin/source/browse/branches/clipboard/qwin-0.7.4-ko.xpi
That started way before panes were so flexible, that’s why separate concerns are combined in one extension. But now Open Files seems to be more superior in terms of grouping and display.
Are you talking about the Open Files widget (in the left pane)? Your mention of tabs is a bit confusing, I guess you could be referring to Open Files entries as tabs or maybe you’re not referencing the Open Files widget at all.
Clarification would be appreciated 
right, Open Files widget – by default left pane
which itself is an extension
Alright, thanks for clarifying. I have some stuff planned for the Open Files pane, hotkeys being one of them. I guess with numbering “tabs” you mean you want to see the number of items under each group?
Here is a screenshot of qwin with tab numbering.
I can switch tabs with hotkey (configurable) ctrl+1 … ctrl+0 and ctrl+q a, ctrl+q b for 11th and 12th and so on, up to 30 or so. (After 30 KO gets quite slow anyway)
My biggest current issue is that file types and path are a tad unreadable.
Ah gotcha. That’s interesting, I will consider that for Open Files.
By the way, not sure if that is part of your qwin addon or something else, but the Open Files widget I was talking about is this one - http://komodoide.com/screencasts/watch/87675282-open-files-widget/