Mg's when told to deploy in a certain direction will sometimes ignore it and deploy the opposite way.
This is certainly a bug I have encountered.
As for vehicle pathing, well it is complicated.
I will take an educated guess and say the pathing is mostly handled by a 3rd party system called Havok, and I am not sure how much Relic can improve upon the pathing themselves.
COH2 is a complicated game, there is a lot of variables that vehicles must take into account. vCOH pathing might be better since the game has less going on, less props, less dynamic objects etc