Hi,
It would be nice I think to have a screen where you could see only “keyframes” you put in a specific track. “Keyframes” would be changes entered in the effect column or in track automation enveloppes.
The main idea is to get an “overall” view of the effects in your song. Because the current “automation” view is limited to the current pattern only. And as far as I know you cannot edit a long enveloppe over many patterns… 
This is could be pretty useful I think…
Here’s a shot of Lightwave 3d’s graph editor, I just faked it a bit to give an idea of what I’m talking about. Don’t care about the buttons and pattern representation… 
Working on some very long piece with a lot of volume changes from one pattern to another made me need that kind of graphic info
Done, that was my little idea. 