One thing that Odie and I agreed upon before he left is that we won’t have a city wall around the next spawn. The reason why is because that wall will soon fill up with protection blocks and will Ale Post all over again. We have no idea how large the city will grow so having a wall is not a good idea until you can really be sure how large the city will be. One thing that you can do is use bushes to create kind of like a hedge around spawn, then you light up spawn to the point where all monsters spawn outside the hedges.
The harbor however is a good idea, it’s always a good thing for new players to explore and a harbor will encourage that. Durin’s Abyss however is not something which can be deemed a public property unless Durin gives their okay.