EVF and video on NEX-7?
There is the option of using an external mic, can you adjust the sound level somehow?
If you really want good sound you're better off using an external recorder such as a Zoom or something similar, and splicing the video with it later. Totally worth it. I've done it with many many videos, and depending on your software, aligning them are a cinch.
I don't have the camera, so I can't comment on the other points. However, its scheduled to arrive in January!