I'm going to change my direction a bit. I'm not satisfied with the current limitiations of onscreen tiles (~100 and you start seeing slowdowns on my machine) So I'll be looking towards having viewing levels. In the inter-airland view your airland with be abstracted to a certain degree, hopefully still conveying the shape and design of your airland. (this should be relatively simple with low poly tiles without transitions) The current work will be the airland level view, with which you can view a particular airland, and anything docked to it. I'm thinking of implementing a closer tile view, where a tile in the airland view can be designated with a zoning type, which affects what kind of things can be built in the tile view mode.
(one of the current factors limiting this is the way in which the current view needs to be updated in order to move in real time in 3 dimensions, with this change only the most zoomed out view will move in 3 dimensions in real time)
The player would be able to designate a tile as a village tile, then zoom to that particular tile, where they can site particular buildings. This will maintain the idea of having the player make decisions as to the layout of tiles in relation to eachother, while allowing a greater density of improvements, (rather than say having all of the assets of an empire being built on individual tiles) The contents of adjacent tiles can have an effect on what can be built and sustained on particular tiles.
I'm thinking I'll try to move towards tracking all individuals, however this may prove unworkable. I am also toying with the idea of resource flows, (rather than stockpiling materials, you would build the infrastructure that would allow you to transport a greater amount of material, allowing projects with ample worker supply to be finished more quickly) however I think I may prefer to keep stockpiles, i'll be considering this further.