First of all, thanks a lot for this great mod! The Ferrari is a real must have in the GTE lineup!
I recently tested the car quite intensively at Potrero de los Funes against other GTEs. I realised that the Ferrari unfortunately has a lack of top speed. On the long straights, it is about 10 to 15 km/h slower than it's competitors which results in 0,5 to 1 s slower lap times.
Also I think it needs more downforce on the rear end. In highspeed corners it is more unstable than the other cars. If you try to lower the rear wing (to gain a few km/hs on the straights), it sadly becomes undriveable, spinning at every full-throttle corner. The front is fine though (in terms of low front splitter values).
Other than that, the handling is great and feels really balanced from my perspective.
Hope that helps a little :)