I know people are looking to use Imerge for various workflows, however ours may be a bit specific. We use PhotoKey at events — capturing, tweaking, printing and exporting — at a very high volume. We've been using it since v4, however Imerge has some interesting additions we'd like to utilize, but currently a few restrictions or missing aspects that would make our application work even better.
Keying Presets - There may be a current way to do it, but to have the ability to set a keying preset and then easily/quickly apply it to a new layer with a chromakey image
Tabbed Windows - Much like Photoshop, the ability to have multiple templates open to easily go between them and work within them
Hot Folders - I know it's already stated that it's not supported, but this would be a critical aspect for our workflow, so basically the ability to set a Content type as a folder instead of an individual image/file