Is the settlement system linked to the main story at all or is it just a side game? Trying to figure out if it is worth putting time into it.
Apart from whatever quests require you to do stuff, like the initial stuff in Sanctuary Hills and occasionally having to build just one or two things for a faction somewhere, there's almost no story involvement. It is a fun distraction though, as all the mega-settlement builders out there can attest.
Unrelated, but had a funny bug occur. Not sure if it was Automatron-related, but went to a settlement that was under attack by Mechanist robots (seems that for the moment, they're the antagonists in every settlement attack) and the hostile Mr. Gutsy that always respawns just west of Finch Farm had joined in, but somehow glitched underground. I had armed Finch Farm's settlers with 5 gauss rifles, several miniguns, and other heavy weaponry, in addition to the multitude of turrets. It was amusing watching the massive amount of fire being poured into the ground ineffectually. I'm not sure if the Mr. Gutsy was doing it, or if friendly fire can do it, but either way, the entire farm's supply of crops got completely shredded in the process.