the watchtower as in season 1 should be in Atlantida and Valhalla at the end of each stage, to collect better items that could be attacked and plundered would be very good and exciting
Watchtower is to guard your empire (Karemdol). Atlantis and Valhalla are foreign territory, you are not there to invade but to help Ariel (Atlantis) and Bjorn/Agnes (Valhalla).
I think SG would let us to put a small basement in these maps,once you completed them.
With 2 farms, 1 mine and another training camp, for watching the land and its people