Just to throw in my thinking on the Tail Rotor positions:
I believe that-
Ideally you should have no tail rotor – but few manufacturers can do that at the moment!
Ideally the TR should be a Tractor Prop – mounted to push onto the tail pylon and avoiding the airless ‘shadow’ caused by the pylon itself.
Ideally the forward rotor should be rising into the Main Rotor wash.
Ideally the TR should be mounted so as to be the same height as the MR in the hover to prevent an additional sideways moment.
I also believe both the Huey (to 205A) and the Lynx (to Mk 7) had problems with TR’s going the “wrong” way and this caused handling and vibe problems which were mainly rectified by redesign. (205A-1 and Mk9)
Rigga