I'd like to see the ability to have 2 microphone inputs for duets. The physical hardware to do this would be one of 2 ways. Either 2 sound cards in a PC, or a higher end sound card that actually has 2 mic inputs (I have a SoundBlaster X-Fi Platinum that has the separate I/O module that provides an additional mic input).
In the software, just need an option to "turn on" a 2nd mic and then duplicate the same options for selecting the source for the 2nd mic and controlling the level for it.

