Transparent Video Window 

Sibelius can do this -- make the video window with adjustable transparency so that you can see the arrange window beneath it. Would be useful for when you're working on a laptop and screen space is at a premium. Would also be nice if you could click behind the video window without selecting it so that you could edit without disturbing the floating "ghost" window on top.

Overlay audio waveform on Midi Edit window 

There is a function in Adobe Dreamweaver where you can design a site in Photoshop then import that image into Dreamweaver as a "tracing" image -- like tracing paper -- and draw over it. The other day, I was lining up midi notes to match the piano recording of an audio file, and I thought it would be great if I could have a tracing image of the waveform directly in the midi edit window. I often add a second midi file to the display to line up notes, and it would be nice to do the same thing with an audio file. The only way to approximate this now is in the arrange window, but I like using my midi editor in full screen mode.

Touch Screen Control Surface 

I would like a multi-touch screen surface (somewhat like Dexter or Lemur) that allows one to control plug-ins directly on the screen. Perhaps it could include real faders and transport buttons, but all the other buttons could be virtual. It should be no larger than a Mackie Control so that it can fit on a desk.

Streamers incorporated into the marker list 

I would like to see streamers and flutters in the marker list. Perhaps they could be an option included in the Video Satellite LE. I can already create streamers using third-party software, but I have to trigger them through a midi track, and it's not as elegant a solution as the method built into Digital Performer.

Set Display Range in Score Window 

This would allow you not to show keyswitches, which are invariably far outside the normal range of an instrument. There should be an option in the same window where you determine the clef to say "Display from C2 to C6" or whatever range you choose.