I recently purchased IOscope and it is a great and very powerful application. I would suggest octave smoothing for the frequency response, I have been experimenting with turning the sample rate down and using less resolution FFT's. It would be so much easier to read the response if smoothing was available.
Also, are there any plans to capture a measurement so it can be seen on the background under a different color or shade and it can be compared to the live trace. this would make EQ changes very obvious and would be also useful to compare delay times between two DUT.