This kind of stuff exists in Eclipse:

But I\'ve not found it in Visual Studio yet. Is ther
Trick is to call Ctrl+F2, then Tab, then Tab, then Down arrow. I've done it with this simple AutoHotkey script when I hit Ctrl+o:
#IfWinActive ahk_exe devenv.exe
^o::
Send ^{F2}
Send {Tab}
Send {Tab}
Send {Down}
return
#IfWinActive
It will show dropdown that is closest to Quick Outline in Eclipse or others.