Honestly, it's just not intuitive enough for me. That said, some suggestions (technical feasibility disregarded)
* Show me referring URLs, not just domains * Click a day on the graph to see that day rather than having to reset the time period on the drop-down menu * Weighted averages: sorting by Bounce Rate is useless; I have lots of these one-off 100% Bounce Rates from one-time referrals. Weighted data so that I can see where my Bounce Rate sucks (or any other metric/Goal) only by those sending some useful level of traffic would be a godsend.