Engineers laying mines

[PlasmaKrab]

I guess that the reasons you gave your engineers not to have engineer units laying mines on-map are the sames that I'm about to repeat:

It would distort the gameplay too much. In defending positions the possibilities to lay mines are already great enough, the FASCAM units are overwhelmingly over-effective, and apparently the code doesn't allow much choice in the amount of mines laid each time (this needs programmers' confirmation). Having many other minelaying devices would give a defender too much of an edge in a battle, for quite a small cost.
Besides there are strong risks of bugs occuring.

Of course it is doable, Listy has come up with a perfectly good Shielder (UK) minespreader vehicle, and has apparently been able to apply the same principle to helos and aircrafts. Most probably you could do the same with infantry units.

Just remind that this thing will never become official.