I think you are on to the right direction but wrong engine configuration. I think the inline 4 will screw up the Buell chasis. The Buell chasis and looks are fantastic. Too me the Firebolt still looks like a new design to me. Even though I put down twins all the time, I think Aprilia, Ducati, and KTM have shown that modern liquid cooled V-Twins can be terrific sport bikes. Did you check out the Aprilia story on the V-4? If you click on that link you will see their new V-Twin bikes as well. Awesome.
The thing about the Buell is that it's not a screaming, peaky Japanese squid bike. The Buell makes torque everywhere in the powerband and produces as much power as people can actually USE on public roads (and no, I'm not talking about doing burnouts, squidboy).
Only when a guy can ride a Buell through all the corners at 10/10ths does he have a right to complain about its lack of power.
Until Buell wins a race people will complain etc. You are probably right but logic doesn't sell bikes. Put a modern engine in the Buell and then race it and win. You could sell several hundred thousand bikes. Till then be content with the 100,000 bikes per 20+ years
Remember longride and Buz are part of W's "you can fool some of the people all of time" crowd. ' Sell it to him. Go for it. longride will ride it home from work on those straight and flat streets of Chicago, slap himself in front of the TV watching Faux News with Bud in hand typing on his computer how putting oil in his Buell every 500 miles is no big deal..
Meanwhile mscuddy is riding a Speed Triple humming Rule, Britannia!