Testers needed.

Regarding divine retribution: previously, it was forcibly taught to all dwarves, now it depends on luck.
I'll make a portal to Lake Island – the third in the portal system near the Sanctuary and on the island, but the approach to the sea will be left as is.

Good option.

The tree near the 3rd castle is in a bad location. The player leaves there at level 18-20. The tree becomes useful when you start to understand that there are few battles left, and you won't be able to choose a level limit. After taking the castle on this part of the map, there is nothing more to do. I wouldn't specifically sail around to increase the level at the end of the map (there, the dwarves might start chasing you). A good position for the tree is either in a place that the player frequently passes (roads near the Sanctuary, Lake Island – the most likely place to move to via the city portal), or at the final point of the map (Lake Island, the dwarven castle behind the blue tent).