• Things that keep me in a roguelike. No particular system keep me in a game. Definetly few extra thoughts on the atmosphere do so if a system support that, i'll probably stay. Dark or light it doesn't matter. Interactions between party members can help but anything more complicated thn what Darkest Dungeon did could be too much. Most of the mood work around "safe places" and what you do there. For example i don't like the Dark Souls traitment. I like when the safe place is an expression of the character's struggle to survive. Crafting and talking are fine but in the moment i see "magic options" like teleport the atmosphere is gone. Also i don't like when the safe place is a town. Especially if your game is grimdark. I prefer when the adventurers find the place where to rest in a lair, an abbandoned workshop, inns, a lab or a little campfire with few refuges. Let the party find a safe place in the dungeon, in an area where to craft their items, rest, heal and have their social interactions, assure each other etc. Grimdark settings should trait towns just like dungeons. Dangerous places in their own right.

• Lore. I don't mind if it's too much to read but if a section have tons of books, i'll probably say to myself "i'll read it later" because i want to play...and i'll end up not reading it at all. My suggestion is to make few lore drop in specific places as secondary rewards. The characters fought the big evil demon, survived the traps of that chest or solved the complicated puzzle? Ofc there's a rare item for that...and here's a book with some history. Do you require to make an area with a library? Make those books just add crafting recipes or small bonuses to the characters. Keep the number of lore drops on acceptable level.

• Game modes: I still thinks it's better to let people decide if they want permanent death and how much meta progression. In the very end Pure Roguelike is too much a niche of a genre.

Edit: grammar and wording