I've been using DxTory for a while, and after reading this forum page I agree with everything requested but I have one more feature to add, that I don't think would be too difficult to implement (but what do I know?). I've been using multiple audio streams because my computer doesn't support stereo mix, but the editing programs and compression programs I have only support one. Is it possible that you could add an option to compress both recorded audio streams into one while recording (or after)? That's the only thing that I think is necessary that hasn't been said. If this is already possible, I'd very much like to know how. Thanks for making the best recording software of the moment.
Rightclick on your avi file and choose Extract Audio Stream.
Now add your missing audiotracks manually into your program.