The Canelloni line combines American and European influences in a light and agile package - the front and rear lights remind me of an Alfa 105 GTV, and the side profile (especially on the notchback and convertible) brings to mind the 1st-gen Camaro/Firebird. All in all, it’s one of the best uses I’ve seen for any of the new-for-4.2 '69 Mobula body sets.
The Strega looks decent and would be a great alternative to an MX-5 or S2000. However, a 2-valve/cylinder DOHC head would have been more fitting for the 60s and 70s - it would be very outdated for the 1990s, let alone the 2000s. As for the Giove, I remember the 4-door version from QFC8, where it was quickly found wanting:
TRX tires are those with a diameter divisible exactly by 10 (an attribute shared with racing tires) - so why on Earth did you use them? It may have been that the rule set did not say anything about them.
Keep doing these challenges bro, especially the QFC ones since they have quicker turn around times. You will learn a lot, and every car you will improve. The learning curve is fucking HUGE with this game, so many different aspects.