here are my .02.
moving the motor towards the front will smooth out the cars steering (twitchiness) at speed as the farther away from the pivot point (center between the rear tires) the motor is, the bigger part the resistance to changing direction (i believe this would be centrifugal force) will be.
the shorter arms by themselves has no practical bearing on camber rise/gain other than to make changes more sensitive, and very little impact on how stiff/soft the suspension can be. the only 'stiffness' would be the mechanical friction caused by the tire scrub (track width change during suspenion movement) vs. less scrub/long arm, which is mostly negated by the fact the car is in motion with toe typically being ran in the rear anyway.
overall, i'm just excited that something other than another 'standard shaft layout' car is coming out (don't get me wrong, i've ran a tc3 for years now).