So hopefully when Patch 9 drops, we could have more suggestions. But here is some items that could be added to HN2.
-Flashlight. We only really saw it in a cut scene, but if it was to be an item, then it could drive off the Guest just like in Hello Guest.
-Sleeping Pills. Sleeping pills could be added and if you put the pills in a drink from that NPC house, then they will feel tried and go to bed.
-Sleeping Mechanic. In the beta for HN2, the player could actually sleep at different time periods of the day. This includes Early Morning, Day, Afternoon, and Night.
-Minigames. This could be a little fun addition. Player could discover little floppy discs and use the computer to player short minigames.
-Raven Brooks Civilians Book. This book would be used to learn the names of some of the characters of HN2. How this book works is that in Quentin's Office Room (The one with the computer), you can press E on a book titled, Raven Brooks Civilians and read on some of the residents in HN2. However, some of the pages are missing and you need to explore Raven Brooks to find them. This could be something that could get updated when a new NPC is added.