How about improving the full-screen image quality in TW4 and adding a button action that allows the tour to be restarted from any scene rather than only from the paused point...before adding features like button sounds that don't do a whole lot to improve the quality or functionality of the tour. If you'll look at the tours on my website (http://www.perpetual-images.com/VirtualTours.htm), you'll see that there is a striking difference in full-screen image quality between tours created with TW4 and those created with an Immervision product. While TW4 wins in the features category, it falls appallingly short in image-quality.
This feature is quite important to my overall look and I was happy to see such a positive reaction from EP. I imagine some features might be relatively simple to improve/change/add compared to others.