I think that Blender devs that are coding could learn a lot from how the XSI curve editor works. And revamp the Action editor to more look like a dopesheet, or add a new editor that is a dopesheet. Especially that you have the object and it’s ‘channels’ to the left instead of the right. (make sense since the timeline goes from left to right).
Having tools so that you can add keyframes or changes their slopes accessible in the UI and not in a menu will speed up the workflow (and as XSI has, that you can type in the angle/lenght of a tangent).
Also… get rid of those F******g quat curves on bones. They should be euler, it’s almost impossible to edit the rotation values for bones now that they are Quat curves. So you end up keyframing your ease in and ease out’s. They could be quats in their math, but users need only 3 curves to edit, not 4.
Anyhow, I hope someone who is a developer will take this and try and implement it. I don’t know how to code myself, and I can only hope that someone would find this useful. This would take Blender to another step in character animation.
Next stop would be how to revamp how shape animation works 
XSI Animation editors, F-Curves and Dopesheet:
