I was feeling the same way about my 04'Busa a few months ago. I realized i wanted another bike. Finding a replacement was another problem altogether.
After searching and searching, i couldn't find a do it all one bike for me, other than the Kawi ZRX. Being that i wanted fuel injection that ruled the ZRX out.
Sport touring, cruiser, chopper? The new Concours came real close to winning but i couldn't replace a my customized Busa with just the connie. I was stumped for a week or two till i heard myself talking to another rider one day. I was saying to him how i was ready for something else but i wasn't sure what. And that the only option that possibly would do it for me would be a turbo Busa.
After realizing what i just said things made perfect sense. I didn't need another bike, i wanted a performance upgrade. A turbo Busa.
Point being is not to rush your decision and to let the right choice happen. It will.
The 1397 is a great upgrade. Do yourself a favor if you do this. Get a street kit and spend the extra dough and get a ported head with some matched cams.