@MickDodge I think you can guess that any performance issues you’re having have nothing to do with how many hearthlings you have – rather, it’s all about your absolutely massive construction project!
How many hearthlings are building? You’d probably have better performance results tackling something like this in more bite-sized pieces. Also, patterned floors (which it seems you have) are more “expensive” in terms of performance than more monochromatic ones. How many floors is the wall structure?
(But also: WOW. Looks absolutely spectacular.)