Be able to copy buildings the player does not have, but manned spidertron has

[DeutscheGabanna]

If you're inside a spidertron that has a given building in its inventory, you should be able to copy that building (ghost mode would be forced, obviously).

[PyroFire]

I don't fully understand what you're suggesting, but i think it's about how a spidertron may be far away with a t3 assembling machine, but your character doesn't have any so you can't use the normal ghost placement thing to order the spidertron to build things.

About all i can suggest is try the blueprint system and pre-prepare your constructions, its current implementation is quite amazing.
Or zoom to other parts of your base that do have the item, etc.
To simply managing your inventory and player-item-delivery a bit better e.g. buffer chests so you can easily grab or deposit commonly used items.