> since we already had the energy and materials rules

Do we? As far as I'm concerned there is no materials rule in OC yet. And the energy rule is still in betaalpha-state.

You see, we have a deadline coming in a month upon which we should create a logically completed, playable game build (call it "demo" if you want). See here. So at the moment developers are not concerned greatly about various rules/goals/environment options (just few of them to give a needed diversity to the gameplay). After that, when priorities are shifted from "total parcour/melee" towards the direction of settlement implementation, there will certainly be a great discussion about which rules we should/should'n have.
Unfortunately, right now I can not tell anything about how settlement scenarios would look because it is still a topic for further discussions. So we will probably have to wait a bit.