One of the often inadvertant unfairnesses of being able to work together with devs in any way is that people pick up valuable info, either earlier than others, or stuff that is supposed to be 'behind the curtain'. Even knowledge of the right input here and there for the right outcome is problematic in a competitive rce environment.
The first blog already has quite telling, as long as they actually mean what they say. "gameplay emerging from the interaction of multiple systems rather than the intentional designs of the developer." This would make no interaction an exploit any more. If the effects are too undesirable (and MA finds out about it), it would be up to MA to change the 'parameters' or code surrounding the interaction of features. Expect way more secrets known to varying degrees...
Ownership, user-created content, inter-user contracts and guilds (corporations with group characteristics) are going to be biggies. Let's pray that the systems are transparent from the start, and way way different from the step-by-step snug-building/veggie boxes etc. Progress, ok, yes, but clarity of pathways in the same way that upgrade materials info is now available for armour chains, for example.
The role of pps also looks to be tricky, if they are to mesh and yet stay somewhat independent.
I wouldn't envy even a superb development team with this task, but would be prepared to join such a team. I don't know how long I'd last at MA, though, if I saw 404s of thinking multiple times...
edit: I see "We are currently focusing on Combat and Hunting; with Mining, Resource Gathering and Crafting to follow." Why write the word combat in addition to hunting? Does this mean pvp is being worked on earlier than M, RG and C above? I wonder what lands will be given lootable pvp status, and especially want to know about space (and vehicle combat), ofc.