So, I want to make a public pwarp-shared board near spawn. The best place to do this seems to be across the spawn bridge above one of the bodies of water in the town. I'd have made it already but I'm not quite sure if putting it there would infringe upon a players build space.

I've put a sign marking where It would be, it is unmissable if you cross the spawn bridge. All it is is a cobble placeholder for now, to show what it would obstruct. If it infringes upon anyone's space it will be taken down.

Just show Chinichi where you want it I suppose, he built newspawn and technically owns the town around it.