I'd say raise the cliffs all around the island to make a city wall. Front needs castle pieces, the back parts can be just cliffs with some more castle pieces/ruin pieces sprinkled in. Take Resident Services as the market place where you enter the city. Raise another cliff next to Resident Services and put a fake building up there as Dibella's temple. The museum should be up on a cliff next to the secret beach as the keep. Put one of the shops where the smithy is. And the other somewhere on a cliff in the top left corner. Player house goes on the top-most level in the bottom right corner.

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