Buildable Seawalls / Quay Walls for Harbours

It would be great to have a dedicated seawall or quay wall that works similarly to the existing retaining walls, but is specifically designed for building harbours and industrial waterfronts.
The current retaining walls are so that structures cannot be built directly on top of them, it can be difficult to create clean and realistic-looking ports. Harbours often end up having awkward gaps or irregular coastlines instead of proper straight quays.
A quay wall could allow buildings and harbour infrastructure to be placed directly on top of, or immediately alongside, the waterfront edge. This would make it possible to create compact ports with straight waterfronts, warehouses, storage areas, conveyors, pipes, cranes, and other industrial facilities positioned neatly along the water.
It could potentially work as a more expensive or advanced version of the filling wall, balancing the increased building flexibility with a higher construction cost.
I think this would be a great addition for players who enjoy designing organised, realistic and visually appealing industrial harbours, while also making better use of coastal space.

I was playing just now and I thought about coming up with an idea similar to this... because you can't build liquid pumps with walls to make it look nicer.