Eh well like the soldier system a Pioneer could simply be hired civs to work construction you que up the order to construction afew forts etc. and garrison soldiers in them and you order them to settle down in anew village with their familys etc.

You could make it quite dynamic able to appoint leaders to forts that Auto garrison soldiers based on their skill *Kinda like the city govenor skill their talking about* Add that to the natural evolution of the roads and infranstructure *roads taverns inn's etc. build themselves overtime along the infranstructure as do farms* And you could create a very realistic yet intutitive system that with afew options in the options menu can be auto done. Planned with a general planning system where you give the A.I a goal like *Build a large expansive system* or *Turtle us with defenses etc.* and then it does it for you.

Or the third option to completely Manually build your system only the roads and natural evolutions occure on their own.

That way for those of us who want depth its there.