In order for me to continue playing this game while we wait for more content (or TDU3, whichever comes first), I personally need realistic (not simulation, there's a difference) and predictable (fun) handling tied with proper force feedback. TDU1 was about picking nearly any sort of fast car, and enjoying any type of driving style (relaxed, showboating (drifting), precise fast racing, chasing, making movies, etc). TDU2 seems to be more about struggling to stay on the road without feeling like you're driving at the limit.
#2 Proper TrackIR support, 6-DOF preferably (thank goodness for cam-hack). This aids in cornering, drifting, checking for traffic at intersections, increases the immersion, and allows us to better enjoy the detailed car interiors. Using buttons or the mouse to look around is much slower, and less precise. In TDU1 when in the outside view, I could turn my head to look behind me, negating the real need to use a 'look behind' button. It made police chases and falling backwards down mountains a lot easier.
I don't view TDU as a racing game, but simply as a driving game - so the driving feel is most important. Bost on TDU1's hardcore mode "as is" while you work on something better if you have to, because you don't have a lot of time before we start looking elsewhere. Keep in mind that TDU1 was the reason that I (and many others from the old TDU forums) purchased a Logitech G25. For the sequel to be this hopeless with the wheel is frankly a bit insulting. The only thing that tempts me to keep playing is the offroading, which is slightly better in the handling and force feedback department.