i hate the midi input in ableton, I love the midi clips though for jamming...but when I want to work fast I dont want to be stretching that midi window up into my channels all the time - bloody pain in the ass that is.
let us select a clip, hit a button on the right (which is placed under the session and arrange buttons) to input and edit midi. simple, easy and clear.
or leave it where it is and put one of them arrow bottons that expands it into the main window.
either way, better than dragging the window