Currently, rendering the hatch overlays can be computationally expensive on the client side with large numbers of multiblocks. This applies even if the multiblocks are fully formed and one does not need to know where the hatches can go. To me, the hatch overlays are only really useful when constructing new multiblocks.
To remedy this and further optimize constructing multiblocks when one has a large number of them operational, could there be a new config option, which, when set, disables rendering hatch overlays on formed multiblocks; meaning "the multiblock needs to be invalid for hatch overlays to show" (#957 (comment))?

Modern Industrialization 2.2.30
Minecraft 1.21.1
NeoForge 21.1.90

I think that overlays should still show when multiblocks are fully formed because one often wants to replace normal structure blocks by hatches. An alternative might be to only show the overlays when the player is sufficiently close.

Can you check again with #994? (Released a few weeks ago).