Facing

I enjoy C&C N a great deal. And although I realise that it is abstracted it does seem a little odd there are no facing or zone of control rules.
A unit can cross an enemy unit front with no problem, and there is no benefit in attacking a unit’s rear or flank.
what are the thoughts behind this?

there are also no rules for formations, changing formations or the zillion other tactical unit manoeuvers that the junior commanders take care of. When you command armies or corps, these things are below your notice and simply happen.

However, you will find that the support rules show the benefit of operational outflanking. 

I would say the ZOC is the hex the unit occupies. The firepower and communications in pre-modern warfare were not sufficient to have large ZOCs.

The requirement to retreat towards the baseline makes being attacked from the rear very dangerous without support and leadership. These factors can be considered to allow units to change formation ad hoc so as to successfully respond to attacks from any direction.

Thank you. Makes a great deal of sense when you look at it that way!