As per tradition, here's a sort-of developer commentary for those that find that kind of stuff interesting! Do note that there will be spoilers in this article, though.

Unique weapon

• The Hyper-Cannon is based on the eponymous weapon from RAGE 2, with some gameplay-related differences. The original gun fires high-speed shots that penetrate targets, and can be upgraded to cause killed enemies to explode. The version in this mod gets its unique trait from this upgrade, along with its ammunition capacity.
• I originally planned the weapon to have additional custom sounds and a longer charge time, but as both are tied to the weapon animation, I had to scrap this idea. The custom firing sound remains, though.
  

• The idea for both the location and the entire mod came to me when I noticed the "empty" doorway on the roof of the building. In an unmodded game, the doorway allows you to see through the exterior walls; odds are there was supposed to be an inaccessible door here.
• I originally planned the location to have transparent windows and distant LOD (along with sunlight shadows), but that made the lighting look very unrealistic in the center of the building.
• The thought of the day in the raider terminal is paraphrased from the Mine weapon description in Far Cry: Blood Dragon. I thought that was so good that it needed to be shared!
• There are three additional entries for the same terminal, which are unlocked upon Prydwen's arrival and when either it or the Institute is destroyed.
  

• In real world, the location is actually named Post Office Square and doesn't have a subway station. The closest station that doesn't already appear in the game is Downtown Crossing, which this location is loosely based on.
• The lighting style in the platforms was heavily inspired by the last level of Metro Exodus
  

• The core idea of this location was inspired by the Government Plane Wreck expedition in Far Cry: New Dawn. Unique assets related to this location even have a "VLP_GovernmentPlane" prefix.
• I originally planned the location to be slightly larger and include both wings and the tail section as well. However, due to how much of a pain in the ass the plane fuselage pieces are to work with, I ended up downsizing it a bit.
• The aircraft is based on real-world Airborne Early Warning and Control aircraft, thus the large radar on top of it. The interior is loosely based on certain weather research aircraft, though they are usually of smaller types in real world.
• The last line of the flight 1120 recording was not in the script, and several variations were ad-libbed by the voice actor. I had a hard time picking a favourite from those!
  

• Gleason Manufacturing gets its name from Gleason Pond, which is located in real-world Framingham.
• Although the assembly line and most parts of the machinery are fictional, they are somewhat inspired by real-world electronics factories and assembly plants.
• Writing the technical lore behind Hyper-Cannon development was rather challenging due to the fact that the in-game Gauss Rifle appears to be closer to a coil gun than an actual Gauss gun (which are two different things). As such, I can't guarantee that the writing is scientifically accurate.
• The prototype pod sequence is rather jury-rigged beneath the surface: the pod is actually attached to an upside down lifeboat elevator (identical to the one at the USS Constitution) to make the pod slow down before stopping. In addition, since physics objects can not be attached to static objects, the weapon itself is placed in its final position but initially disabled: when the pod comes to a stop, the weapon is enabled. You can actually see the weapon pop into existence if you look at the inner pod from the side.
  

• I've wanted to create a dungeon with an ambient radiation hazard (like Vault 34 in New Vegas) for a while, and this location provided the perfect opportunity for that. It took me quite a while to achieve a balance where it wasn't neither frustrating or inconsequential, though.
• Originally the roles for Decayed Reactor Site and Decrepit Factory were reversed: while the key would've still been in DRS, it was meant to be a rather standard dungeon in terms of difficulty. On the other hand, DF would've been a late-game dungeon with heavy turret and security robot presence. I switched the roles when I realized that the current arrangement is much more likely to let the player learn of the unique weapon before they find the key.
• The location used to have a different color scheme - it was originally white and yellow, similar to the Outcast Outpost in Fallout 3's Operation Anchorage. It ended up looking far too clean and bright for this location though, so I decided to go with gray and yellow instead.
• The medical lockers found throughout the power plant were heavily inspired by those found in The Long Dark.
• The safe exposure times given at the various door terminals are based on real world: United States Nuclear Regulatory Commission has set the maximum yearly limit at 5 rem/year (=5 rads) for radiation workers. For example, the ambient radiation just inside the warehouse is 2 rads/second (without protection), and therefore you can reach 5 rads in two and half seconds. It's likely that this limit would be much higher in the Fallout universe, though.
• I was also considering having the most intense radiation hotspot to be an Elephant's Foot-like basement room underneath the reactor, but eventually decided against it in favor of having plenty of space for the final ambush.
  

• I got the idea for the backstory when I was playing The Long Dark, in which I ended up setting up shop in an abandoned prepper bunker.
• Since most other locations in this mod are balanced for mid to late-game, I decided to make this place a little easier to even things out a bit.
  

• This location was originally also meant to get an interior, but the idea was foiled by the fact that many of the Deco pieces the building uses do not have interior/two-sided counterparts. While I could work around some pieces, the rounded corners in particular turned out to be impossible to replace with vanilla assets.
• This location would've been balanced for early game, and it would have various mutated bugs as enemies. The goal would have been the evidence locker where the officers stored various weapons and other illegal items before the Great War.
• Notes and terminal entries in this location would have told the story of the police officers who tried to keep order immediately after the war and then regressed into raiders themselves, along with the story of a cop who detested that turn of events. I didn't have a chance to flesh the story out before I ended up cutting the location altogether.