Hello Deskel, much obliged to your response. You seems like a Lore master to ask.
I brushed up on some Happy Events I've even encountered and fashioned a few more theories. I'd like to hear what would you think of them.
First, the association between Nozumu and HOPE is very ambiguous and I always presumed they were one entity with different perception. However, I've found tons of hints suggesting Nozumu was already dead (God is dead) and tried to come back at any cost (Poor John, do you have any idea why it's User 2 who erased his personality? To prevent infos as much as possible from Sensei?) while HOPE is clearly alive and lived with his angels at the bottom of everything. (room of clocks) I would like to assert that "Something was buried underneath" should be carcass of Nozumu since it's always mentioned in or around Old District that was under his influence (Probably Tojo's Ramen was an exclave of User2 to spy on Nozumu?).
Anyway, I'm starting to doubt if HOPE is the emissary of The Concerned God- That is, if I have to guess on who User 3 is, it's highly possible that the narrator who always encourged and comforted Sensei was the authentic identity of it. My intuition told me it should be Sekai now that she's the only one knew many secrets of Sensei. And Sekai held grudges towards Maya, therefor suffered 61 (old memory remainder of Maya?) a lot in room of clocks.
Furthermore, HOPE, Maya and Sekai the narrator all had implication with the Sky. In the end of First Beach travel where narrator told you a story tree. One of the flash image depicts countenance of HOPE with many smile faces in sky above a tree struting from ground. HOPE also called himself "the feathered kind" and in Trinity III, Sensei said to himself that he started to lose hope, he could never ever rise his head, at the very moment as HOPE started to talk in lower case. (sized by Nozumu or Sekai?)
And it brings out the question about which god does Yasu pray for and entrust with. At first glance she was obviously a follower of Nozumu, either because of her purpose of letting Sensei defiling every girl and ascending to an angel or her parables with "The one with many eyes", one of the epithets attributed to Nozumu in Happy Events. We nevertheless only saw symbol of Cross and Cruification in HOPE's realm. "Sound of cicadas", her introduction event, was a phrase used by HOPE to describe himself. Nor does she like summer much. What if Nozumu has always took the control over HOPE and pretended he was User3? What do you say?
It all jumbles up. Now, I simply cannot get my head around it. Things no longer add up as they used to be...
Keep in mind that in Yasu's and The New Hope's church faith, there is no death:
A god being dead, especially the one she seems to follow would equate to a god being on a second plane of existence. Frankly, her story about the person who was born blind, sewn eyes to himself, then died and saw through the lives of others, seems to be the origin story of her god. This was mentioned in Yasu's 'Sakura Season' Event:
In other words, her god seems to have became a god after it died. Sensei's brother, Nozomu, dying, then HOPE showing up could be why they are equated. HOPE can also translate to Nozomu in japanese.
HOPE has also been mentioned to have many eyes:
Like Yasu's god:
Sensei and The Player can only apparently see two of those eyes.
John also seems to sound like HOPE:
So, if there is a ressurection going on, it'd probably involve HOPE when it comes to John.
Btw, Yasu loves the Summer:
But does not like the Winter:
Fun fact, if Yasu is wearing mostly black, it's probably Summer. If she's wearing mostly white, it's probably not.
Overall: It's very likely that the god called Nozomu, The Callous god, and HOPE, as well as Yasu's god are all the same thing.
Now, as for the confusing parts, I think you've conflated USER2 and USER3 with other things. USER3 is Pareidolia, The Concerned God, and The Dark. It usually talks in lower case. HOPE doesn't. HOPE has had seemingly nothing to do with USER3/Pareidolia so far.
It also probably wasn't USER2 who affected John. John was presumably talking about The World Itself, hence it mentioning "tendrils"
And Yasu seemed extremely scared of the tendrils of sky:
Which seem to come from The World Itself, as that was the thing Yasu was talking about at the time:
This might be the thing that scared John and made him incomprehensible. Albeit, the World Itself is somewhat of a mystery. It seems to be related to The Sky, and Sekai though. It also seems to be somewhat HOPE's opposite, if not perhaps it's Devil, but that's just a theory.
Overall: HOPE shouldn't be an emissary of Pareidolia/USER3, and USER2 probably didn't do anything to John. Yasu also loves the Summer. As for the Tree stuff, that seems to be USER2's thing, but all the gods have some relation to the tree:
And the universe itself is a forest:
