RE: Nose gear placement
As noted moving the main gear rearward and further aft of the CG will will increase the force needed to rotate for takeoff and cause takeoff attempts that are characterized by jumping off the ground suddenly and at steep pitch attitudes. This is definately something you do not want to deal with especially with somewhat oversized engines and precisely when there is substancial 'P' factor present which often can result in a snap roll into the ground.
John