similar situation on my current map, built an outpost that is connected by a road and wanted to expand the road network. then some spitters attacked, and my drones went swimming in the acid pools on the road :-) :-(
MY solution: first i used only Klonan's repair turrets to repsir drones along the road, but after they got the research to also build items, i now have them along all my roads in a group together with a large power pole and 1 or 2 lasers, and they all protect each other and the drones on the road, also repair drones quickly when spitters still got to spit on the road before being killed. and in the outpost, even large new setups can be built with blueprints by the turrets teleporting all needed items from my mall :-)
just now, i am about to build a road by using a blueprint with this setup, and the repair turrets will build everything.
my only problem : the repair turrets and my construction drones are racing who gets to place or deconstruct something first. most of the time the turrets win, but when they are out of power for a moment, i ended up with the drones leaving it to the turrets, and the turrets not deconstructing, and thus i had to give the deconstruct order (with the vanilla tool) several times until all tiles were gone.
I'll have to disable the drones next time i try something similar, or is there an option to automatically disable the construction drones while in the range of a logistics construction area (from vanilla roboports, Klonan's repair turrets, or any other modded construction areas like "construction towers" mod) ?