Surprise tactics mean very little when the whole defending force can teleport just as easily as the attacking one

All it needs is a scout at each outpost. The counter-'tactic' is for the defenders to declare war on any attacking guilds at the same time. All that's going to happen is every OP is constantly under 'attack' and only a small fraction of those are genuine. Not very immersive.
People are taking declaring war too lightly as well. I wonder if anyone attacking an outpost would have the bodocs to post here? I know the serious ones would who have stopped for a second to think of the consequences.
Personally, I don't think a guild should be able to declare war on more than one outpost at the same time. If an alliance of guilds wants to hide their true target then fair enough (if they think they're too weak to win by normal means).