Any mods for that?

square - some area. not tile. other was correct.
One of the main problems - belts. Belts that will no longer be used easily mess up all new paths. Overlaying spaghetti belts on top of old belts going crazy. It's impossible to untangle afterward.

Also, electric pole duplication happens frequently ...

its pretty big base. And ofc not everything works perfect. Somewhere wrong belt, somewhere need to put extra assembly, somewhere need to change ways and etc, etc. In 90% cases its rly small changes, but many. In different parts of base. Bug tracking of base if you want and fix small problems. So its ...

and we go back to delete all base again or write changes of each part of base to notepad... that process of rebuilding can spend hours, in that time many parts of base will not work, cross planed delivery will be ruined, other planets will not work too...

atm im using ghosts of lamps to mark empty ...

Amazing answer. I said about have tons of trash after apply blueprint and you recommend place blueprint and delete trash... How i will delete it? by hand? delete by deconstruction? delete what? base on 200k+ objects? write to notepad each changed object to manual deleting?

I play in multiplayer, time-to-time we play alone and ugprade bases. How to apply plan with remove everything what not exist on plan? Delete everything on planet and apply plan is not ok solution at all.