(Hello Blender Team, I'm new here so I don't know your rules. However, I wanted to give you input. Please help me on that. I just tried Blender for the first time and as a professional User Interface Designer, I would like to advice you guys on the Dope Sheet's UI)
The Dope Sheet window is a very nice way to get an overview of the animation. However, editing, in its current 2.76 version, is really cumbersome.
Mouse's paradigm usually involve that clicking an item selects it and clicking an empty space around it deselects the item. Selecting multiple items is usually done by click-dragging the mouse around the desired items or shift-clicking / shift click-dragging over individual items. Moving items is done by click-dragging the selected item. Duplicating is done by holding Alt while click-dragging selected items.
However, the Dope Sheet respects -none- of those principle, making it almost to immediately understand until the user try hard to grasp the unusual concept. Thus, by definition, the Dope Sheet window isn't "user-friendly".
Would it be possible to apply those basic concepts to the Dope Sheet window? This would greatly help newcomers stick to Blender.
Let me know if you have questions.