Since this is a larger landmass in Maine I got to thinking that the introduction to another vault is a strong possibility. Here is my experiment.

Residents inside are only able to communicate to each other using terminals. They never see each other at all. The catch is only once a year they can get together (to reproduce etc..) but then back to the rooms they are locked in. That is what they were told anyway, and soon will be a known lie. Plot twist is, the computer AI generates the fake one day event and the residents never leave the rooms. So they think they missed out. So you can tell they absolutely went crazy and all they had was the screens to entertain themselves, for better or worse.

Just an idea and like to hear what Vault-Tec experiment you want in Far Harbor!

Reading endless terminal convos doesn't appeal.. A vault full of canibals and a mystery would be cool

Being the single largest landmass expansion they've ever done I'd be disappointed if they didn't at least add a couple vaults. As for ideas don't have any in particular but I would like to see something horror themed.

Maybe, but I don't see why Vault-Tec would have built a Vault in Far Harbor.

Because they built vaults for a living?

And other than the conspiracy, there was no real rhyme or reason to their plans aside from building what they wanted to or what they got paid to build. So there are zero limiting factors on where a vault could show up.

So maine then? Hmmm how about a Vault that's partially submerged and was being used to genetically engineer a species of gillmen in order to colonize the oceans. Yadda yadda and horrible accident with fishmen murdering everyone in the vault.

So have both scientists and fisherman try and make a new species of ocean enemy that once you open the vault everything overrides leading to the oceans being near impossible to swim in without being attacked. haha

Id rather they add an underground or underwater military instillation. That did biological, mechanical, and "mystical" experiments. It is set on an island after all. It could be a place all factions are searching for.

New vaults would be nice though I wouldn't hold my breath. If they do add new vaults, they should be dark and creepy like the FEV lab in The Institute.

I would love it if Bethesda made a vault using that horror atmosphere they are so good at. Make an empty vault with plenty of world story leading up to something [censored] creepy.

Several probably. Hopefully at least one like 81.

I just want there to be a door obviously leading to loot only to be opened revealing another door slammed closed with spray paint saying: "[censored] you!"

That was awesome in fo3.

This would be my wish. Something "Bioshock-esque" where you pieced together the event from environmental context.

Honestly, the horror vibe is hard to nail down in Fallout, which seems odd doesn't it? For instance, a certain place in the north-east corner of the map failed to deliver a horror vibe even though that is clearly what they were aiming for. It was creepy I'll admit but not in the "what could it be" sense, because Fallout has a limited enemy set list. I think if they had a Vault where they introduced a specific new enemy or threat and built up to the reveal throughout exploring the vault, that would be amazing.

Vault of forbidden knowledge relating to something ancient and outside our realm of understanding. AKA Cthulhu vault please.

There will be at least two vaults.

There is already a door like that in the Commonwealth, and it comes with a free Sentry Bot. It's a combo deal.

they could have a vault on the moon if they wanted to