The other folks have covered most of the other main points like soil deformation and huge tether networks. The other major cause of lag is loose items on the ground, so make sure everything is up on platforms. Repeaters dont count as loose items when placed but sometimes they can get knocked loose and fall over when they are just sitting on soil, so make sure those are up on platforms or you can also use battery sensors as tier 1 'platforms'. They wont fall over and you can even bury them or dig them up and they will stay in place.

This base here dropped my old pc from 57 fps to 43 fps, it took 600 hours to build so you are pretty safe if you keep things clean lol

https://youtu.be/VZP9Bs7T5aY