A quick thought: in a lot of programs, control + up / down will move the cursor up or down one paragraph. So, control + up / down in DM should move the cursor to the next / last change in indentation.
A lot of programs also finish keywords when you press tab. That would be really nice.
In response to ThreeFingerPete
Trouble is, there are already functions for those shortcuts; Ctrl-up/down scrolls the code window, and tab inserts a tab. There are circumstances in which you might want to use those shortcuts how they are now, especially the tab key.

I'm not against adding new features, by any means, but I think they need different shortcut keys.
In response to Crispy
Oh damn, I forgot about that. I always use pageup / pagedown, or just holding down the up / down key for a while.