Yes, Hz doesn't matter.
You can limit the FPS ingame anyway. Minimum should be 30 FPS, 60 FPS is ideal. Anything above 60 FPS is fine too.
- Hidden Reputation system with Kerfus(O)
- A way to upgrade Kerfus(O)'s AI and make Kerfus more "sentient", where Kerfus can make their own decisions: say no, decide to be your friend or hate you, become your ally or helps the "enemy" to sabotage you, help protect you or joins in with the enemy.
- More ways to take care of Kerfus(O) when he gained "sentience", more idling / free time / hobby things to buy or build/craft for Kerfus(O) to use. Furniture and Beds to craft / build for them. Maybe even be able to give Kerfus their own room.
- A "BFF"-Necklace for KerfusO to wear.
- A way to be able to toggle Kerfus(O)'s light without the PC.
I can't give you a certain yes on that, but I think it is possible to soft lock yourself out of certain events.
However, those are mostly easter egg kind of events that are not story relevant, see it more of a bonus content that you missed that might not even be canonical to be in the game to begin with.
Like, let's say you lose one of the Metal Tiles forever, you won't be able to do "a thing", but that thing is not relevant in any shape or form anyway.
There are a few more things that you can permanently miss, but those have no impact on whether you can do something or something happens or not, so don't worry too much about it.
Also, there are many other things that can be missed, so several playthroughs through the Story Mode to see them are not too uncommon of a thing to do. (or play the Infinity Mode which itself also disables certain things)
- A muddy / swamp area with lots of swamp plants and water lily pads and water that has a very short view range. Requires Mud Boots to be able to traverse, otherwise the player will be slowed down and might get stuck. (repeated jumping / hook needed to get unstuck)
Traversing there without Mud Boots increases the Stamina drain. Green/Brownish mist/fog even during daylight.
- Fingerprint Powder & Brush to make stuff visible if you have the feeling that something changed even though you didn't touch anything.
Maybe with a transparent film to copy the fingerprints to the PC.
- A "Déjà vu"-Event, where a certain day repeats over and over until you manage to break through the cycle to the next day. (at midnight it teleports you back fade-in/-out to where you were when it started, with signals, drives, items, money, hunger and stamina also resetting to that point)
- A Tinfoil Hat to protect yourself from mind probing and mind control and aliens and stuff.
- A Vintage Photo Camera and Photographic Film 35mm and a Darkroom (buildable) to develop the film in. With special chemicals you've researched and compounded, you can make things visible that the Digital Camera can't capture.
Long exposure (tripod) or certain things and places might also reveal something new.
- A Slide Projector, to view the developed films. (with that mechanical & light bulb sound, like in the very first X-Files episode)
- Also the possibility to save digital photos onto film to use them on the Slide Projector.
- Also, allow Custom Films to be created through the assets folder. (put picture into asset folder -> then use same method as putting digital photos on film)
- Colour Filter (round plastic glasses in front of the projector) for the Slide Projector, to filter out certain colours and make anomalies visible.
- Same thing but this time a Vintage Video Camera with 35mm Film (24 FPS) allows you to record videos (handeld) and areas (tripod), as above. (no audio)
- A movie projector for 35mm film. (film roll & light bulb sound when playing the movie)
- A craftable Wooden Stake and Garlic, just in case.
- Honey.
- Ants, Ant Hills.
- UV Light Lamp (handheld and stationary) to reveal liquids and stuff with.
- A Cheese Fondue set.
- Random VHS tapes that can be found on the map with spooky content in them, require a VHS Player to watch. (if clipping camera video footage is possible in the future, allow the VHS to be used to save the footage and rewatch them on TVs?)
- Diskettes and big Floppy's with secret information on them / scary stuff, secrets, etc. that can also be found around the map. Requires an old PC with a 3.5" and 5.25" diskette drive. (and a DOS looking OS)
- Also maybe combine them with signals or special signals, where the drives information has to be copied onto a diskette and then inserted into the old PC to filter out more information.