Thanks, Light.
Whatever happens, there will be mooring for your boat and your house will be close by. That's a priority! The house and mooring may well be further to the east, so you will gain an uninterrupted view of the sunrise.
Quin's flooded cottage is probably due for demolition -- rotted wood, serious subsidence, to say nothing of the health hazard it was before all that happened. The lighthouse is likely to be needed on the west-to-northwest shoreline to warn ships away from the cliffs, and to provide some shelter for Mermaid Cove where the pirate ship will anchor (it is still on the move).
The sky island intended for my new home has been taken down in preparation for all these moves.
One thing that has emerged from working on different levels (ground level, sky village, building level) is that it helps if all the land is set to the same group ownership. What I was finding when trying to place islands at the building level is that they often overlapped with individually-owned plots, which could cause problems if prim limits for those plots are exceeded. If all the land is group owned, the whole 15,000-prim sim allowance can be spread out over the various plots.
Each cottage can still be on its own plot and named accordingly -- so, for example, Nyn's cottage could still be on a plot called 'Seaside Cottage'.
The doors and windows on the cottages have security devices that can be set so that only the person living in the cottage can unlock or open them. Would this be enough to maintain individual privacy?
Providing you are a member of Devokan Estate group (and if you rent there, you are), you can set your 'home' to be anywhere on the sim, including your house, i.e. it is not necessary to 'buy' or 'own' a plot of land. This in fact mirrors how Quin's landlady has set up the rooms for rent in Port Babbage.
I didn't realise all this when first setting up the cottage rentals -- sorry.
I'm putting this out for discussion. If people would prefer to keep individual ownership of plots, that's understandable and fine!
. New buildings can be built upon existing ground, old buildings can be moved or taken down. 
Wow ametist! You really did your digging! Thank you for the pictures. I like your idea with the split bit of land on its own. You really help put things in perspective with those drawings. Very nice. 
If we can endure this time, I believe Devokan will emerge on the other side a more vibrant and interesting place. One that we have created together!