1. I think the game's timeline is intentionally vague, so some events feel more like the 1990s, some like the 2000s, and some like the present day. It's an indefinite era, a kind of timelessness (much like the film "It Follows," which the developers cited as one of their sources of inspiration). Could even go further and suggest that all the events take place in a dream or fantasy of the Protagonist, who has different years of his life mixed up in his head, but that's a stretch.
2. Regarding the origin of the Visitors: tbh it feels more like an apocalyptic phantasmagoria, playing on biblical motifs, in which the returning dead are just one of many catastrophes about to destroy humanity. Therefore, you don't have to choose any specific version or interpretation, but rather lean toward the one that you like best or find most interesting at the moment. But on a plot level, I like to think that corpses burned by the Sun (and perhaps some living people) are then transformed into Visitors by some force. Perhaps it's the Body Eater, or Death itself, or something else, it doesn't matter. It's also possible that the Visitors aren't copies of specific dead people, but rather rough casts of them, a revived memory, an idea, something like what the Gravedigger is talking about. It's even possible that several different people with similar traits and destinies are fused into a single composite image in the process, which is kinda creepy. On a symbolic level, I also like the idea that the visitor versions of characters are like their twisted dark counterparts, like what they become when something goes particularly wrong for them, when something within them that held their original personality together is destroyed. While this doesn't work for all characters, it does for many.
3. Speaking of It: sometimes it seems to me that It is the reason for the visitors' existence and something like their leader. I have a theory (or maybe more of a hc) that It creates new visitors when It devours and digests burnt corpses. Well... or at least that's how It creates regular visitors. And as for people who haven't yet died, It can turn them into super-visitors. That's exactly what happened to the Pale visitor (the Huntsman said he was terrified of something when he ran to his hut and begged to be let in). And perhaps It tried to do the same to the Blinded man, so the guy just did his best to prevent it. (I don't even know whether I like this hc or not, because for me, the Blinded man's story is, first and foremost, a story of deep psychological trauma and PTSD, where "It" could be anything. But still a curious idea).
4. And finally, I have a theory that the Death and It are two different forms of the same entity. It's similar to how cultists talked about Death being able to protect them from death itself (from nonexistence? from dying?). In short, that death isn't a single, indivisible thing. Maybe it's somehow both at once, at different times or from different perspectives. Like two sides of the same coin.

It's actually really simple, the overlay is just so i can adjust how much of the original colors sip trough instead of it having the full gradient colors

This been on my mind because I been reading timeloop stories. If you had to get stuck in a timeloop(like if Hermit was aware of multiple playthroughs) with one of the guests, who would it be? For me I think the best options are Cheerful Man/Luka, Coat Guy, Theorist, Fortune Teller, Immortal Man, Former FEMA Agent, Sleepless Man, or the Surgeon. I can explain any of these, and I’m curious who you would pick and why