I do like the concept of the shards. Likewise it would be nice that private servers could be inter-connected.
For example, different computer clans (yes, I am old) or companies / departments have private servers on which they compete against each other.
It would be nice if private servers could be connected through portals to "raid" another server.
To make it fair it could be changed that once you go into "domination" you cannot interact (freeze code? you committed to an attack, now face the consequences) as well.
That attacker and defender need to rely solely on their code.
A delay would solve no online/offline problem.
Also, I am in the role of an underdog and not gotten so far yet. But can't you already cancel a safe mode by nuking the room? (From the docs it reads as a nuke cancels the safe mode?)