I too am currently suffering from crashes in specific spots, and have also tried everything under the sun to fix it; even such things as removing inventory to try and see if there are corrupted items (though KEY items are impossible to test) and dismissing/changing my companion. Though, it seems those 'specific spots' are spreading, and many in number. I haven't been playing that long (14 hours? ~level 9), so I don't know much about the areas or quests, so forgive me if it's the same as you all have been discussing. I will do my best regarding screenshots of current/completed quests, exact spots of crashing, and my little knowledge of things.
From what I can recall, I had never been to most of these areas prior. Something to note though, was I did experience a crash at Sanctuary randomly near my crafting benches; not sure on that one's cause, but I was definitely in a spot I had been before.
So far, my crashes have been around/near [southeast of] Kendall Hospital (C.I.T., as everyone else) and the broken bridge toward the landmass Diamond City is on (not the same as everyone else).
Here's my crash "data" (Note: don't have "permission" to post links, so delete the 2 spaces):
https:// youtu. be/kG_WRre9cl8
Shows: Currents quests, 4 places I've crashed, final frame of crashes, and that Fall Out Boy makes...ahem, "good" music.
Here's hoping there's a fix soon! Cheers!