Chaos structures.

I don't know, but it seems that way to me! Before, the central tower was built first, but now three are built simultaneously!

No... the central tower definitely provides a bigger bonus... about twice as much...
By the way, I hope that in the courses, the damage from the castle (citadel) is greater than from the stronghold... (even if you attack in melee from different sides of the fence...)

And the fact that all towers are built simultaneously is a bit disappointing... the citadel has practically no bonuses... it's just an intermediate stage before the castle.