I saw your post and had to respond. I have ridden just about every major brand and model of liter class sport bike available, to include BMW, Ducati, Augusta, Aprilia and most of the Japanese bikes. I love the power to weight ratio, the incredible acceleration and as you mentioned the flickable nature of those bikes in the twisties. Beyond all of those characteristics, all of those bikes share one important common trait....extreme discomfort!
If you are willing to forego comfort while riding in a tuck that brings consistent pain to your wrists, neck, back and knees after relative short periods of time in the saddle, then the sport bike may be a substitute. Speed through the corners is fun, but the long ride to those twisties is a bummer, no matter what kind of seat you apply. I have been there and done that. I even thought that a compromised ergo bike, sport tourer like the Yamaha FJR1300 would be good, and it was fun but still not overly comfortable for two up and honesty, somewhat soulless.
So, for me the Rocket III is the unique, comfortable, fast cruiser with a long tradition of putting other bikes in its class to shame. As the other guys here are saying, don't expect one bike to do it all, they don't exist. Find out what you do most and pick a bike to that thing....mine is fast comfort and great looks. To each his own.
j