Online racing is rubbish, PP system is broken, the inability to change tracks and settings in the lobby (a feature the predecessor had) means this franchise has gone backwards.
On the actual simulator front, the countersteering mechanics of the vehicle is problematic and inconsistent, constantly finding myself over correcting slides or having to make multiple corrections throughout the corner. I have no such problem in real life on real circuits in real cars so I'll deny that it's a problem with my driving. Perhaps it's a non issue on a rig that has G force inputs (hydraulic rams) but on a standard stationary rig where you can't feel the inertia of the car you can't make the countersteer mechanics so unforgiving.
It's a shame that a game we've been waiting so long for is so disappointing.