. .. .The carbon fork is nice (but fragile, scratches can render them unsafe. . . .

Oh pleeze, enough with the 'carbon is fragile and scary' silliness. I've yet to see a scratched carbon frame or fork that was unsafe merely due to a scratch. In our shop we see plenty of old carbon bikes that are well worn and still plenty safe and ridden regularly.

And FWIW, the 7.5 is indeed a better bike. Lighter and better components. Does it cost more? Yes. That's usually how it works.