When i had 1000cc (Sports) motorbikes, I genuinely found them better to ride safely than the 500cc bike I started with.
I went on and took advice from an Advanced Rider/course and the mantra was "the throttle operates in two directions!".
A Morgan any Morgan (as per any car) is unsafe, if you just open the throttle - not taking in the surrounding roads conditions and your own ability, into account?
However, I would 100% prefer to be in a more powerful car say 375bhp than one with 75bhp. Yes (for a while) you can boot the 75bhp car - as if it is a Spanish Renter - however, driving smoothly and responsibility and overtaking the odd lorry (on an A-Road) with confidence - can be safer - from my biking experiences.
So if I were lucky enough to own a PlusSix...I would 100% take it on track day - and experience, it's and my limits...and learn from the experience (planning to do so with the Roadster this year).