Hmm... in terms of the dialogue, it's not always necessary for the NPCs to have distinct voices in RPGs, just there at least two or three of them all seemed preoccupied with identity (who is me and am I you or myself sort of thing) and a lot of them were interested in the environment but specifically how, nonsensical it was? I think that for me was what felt a little same-y, or, not that they are preoccupied by the same thing but that they do it in the same way. Nobody is like, "oh this HAS to be a dream", or someone else thinking it's like, a trick or a punishment. I mean again, it's not strictly necessary, but besides the guy who tries to fight you it feels like everyone is more thinking about what's going on than anything else, and in general people will have pretty different reactions to things, even similar things. Even things like crying, or going silent, or asking for help. Just my opinion though.
Well, mostly I think the feeling of same-iness could be more the way the dialogue is conveyed rather than the language itself. I think because it's all typed in with minimal pauses, it feels clunky even when it doesn't need to be. And often it makes their dialogue feel more similar than it is, even when some people use longer sentences and some more fragments. I think some use of a message plugin which pauses during a passage, or even just spacing out some of the lines would help with the impact if that makes sense. The dialogue does have a good rhythm, but it's paragraph-like format kind of hides this. For example:
"It is... by no means... a physical house, but... are we? Are you? What is physical? Is it thought? Is it the void? Is it the soulful tune of despair? I do not even know who I happen to be, and yet I feel, emanating, pulsating, this... this..."
This passage includes a lot of sentence fragments, which actually is a very fitting style for this game! However, I think it works better when spaced out more like poetry, but it doesn't even need to be that much. For example:
"Is it... by no means... a physical house."
"But... are we? Are you?"
"What is physical? Is it thought? Is it the void? Is it the soulful tune of despair?"
"I do not even know who I happen to be, and yet I feel, emanating, pulsating, this... this..."
Not that exactly, but I feel like it reads a little better? Especially in an RPG format where the text boxes tend to be smaller anyways.
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anyways, sorry for the long comments! I hope they're able to be helpful at least. Thank you for letting me know about sticking to the edges, I'll try to make my way into the house and possibly comment about it if I'm able to get in and see anything new.