first of all you need to experiment with this without doing anymodding, then use galaxy forge or map maker to make a very small map. this question really is not a modding question

Build......depends on your definition of "Build"

(Spawn, yes, Build, no)

As for Move orders, NO.

Wraith Mod Productions (Me and shadow mastiff) already have a mod like this under construction, and almost finished called, Bridge Comand.

Forums: http://wraithmodproduction.enjin.com/

waypoints can be set on anything from a FIGHTER to a STARBASE. And anywhere in the map. You can even have three planets with three frig factories each, all rallied to three different caps, and spitting out Cobalts like mad.

The end result- probably heavy losses but target saturation for the enemy (TOO MUCH TO SHOOT AT!).