I would say that that heavily depends on the actual mission concept.
For instance i made a mission ("Defend the base") that would heavily suffer from such restrictions.
While i agree with what you propose, i also want to point out that all that can be scripted.
What is needed is a stable core module for the basics that allow (like already it did in Arma2) such extensions. This way the mission maker has full control over the how and why of construction limits.