Actually, the Hayabusa is a very "sensible" sportbike. With its particular ergonomics and long(er) wheelbase, it's a great road bike, with a lot more potential for long days in the saddle than the "race replicas."
I've even added a trip computer, luggage rack, and Corbin saddles to mine, and I have one heck of of a "hypersport-tourer" (let's call it "tourabusa," eh?). One of these days I'm going to take it on an Iron Butt SS1000, just for the heck of it.
One guy I know (mjames -- Michael Glass) from the BMW world did a 100CCC "insanity" ride on his 'Busa -- that's across the US and BACK in less than 100hrs -- on his '02, 2-up with his girlfriend and, like, 60lbs of gear.
As for "too much bike," the 'Busa is built for the road, not the track. The ECU detunes the engine at lower RPMs in lower gears for better traction and manageability in the real world. As a result, it's a very tame bike until you uncork the genie in 3rd or 4th gear at about 6k RPM.
The only problem you're gonna maybe have is with your back and maybe your wrists. If you're used to the upright positions on the touring bikes, your instinct on a sport bike will be to put your weight on your wrists, which will cause all kinds of fatigue in a hurry.
I learned when riding my (former) BMW K1200RS to support more of my weight with my hips, also keeping my elbows bent so that I don't have to shift my weight so much to turn the bars. This is a little more work for your hips and lower back, but it makes riding the 'Busa or other (larger) sport bike much more fun and liveable.
Aldo, the footpeg position is much higher than on your touring bikes, which could take some getting used to -- that first takeoff of the morning is still a little tricky for me sometimes. Still, the Hayabusa's setup is more sane than most sportbikes, and you can spend quite a few hours on it.