Colonists who experience negative social interaction in the hours before the go to sleep have higher chance of negative sleep/dream events, possibly spending the night blaming themselves for perceived faults, dreaming about getting into a fight, or laying awake (disturbed sleep?) thinking about the event.

Bad dreams have a risk of leaving colonists with a sore back or neck when they wake due to sleeping poorly.

Good dreams may rarely provide a small, short term (2 day?) boost to research speed from dreaming of possibilities.

Nightmare mechanics with each pawn having a different, most feared thing (item, creature, etc).

Psycasters being able to materialize the most feared thing in front of a targeted colonist (only visible to the affected person, kind of like inducing sleep paralysis) which puts him into a downed state for a short amount of time, and provides a mood debuff for him too. Mood debuff and downed state are longer for people with traits that make their mentality weaker (psychically hypersensitive, psychically sensitive, volatile, nervous) and the other way around for people with traits that make their mentality stronger (psychically dull, iron-willed, steadfast). People with the psychically deaf trait are immune to this psycasting ability.

@Daunmi, I really like the last one. I'm planning for my dreams to sometimes give a inspiration but this is something else... I will think about it thanks!

@Smelly Fish, that's a cool idea for another mod. Maybe next time I will make a mod about dreaming abilities OR make actual new class of psycasters called dreamers. They could recharge when they sleep and learn new "psycasts" when they dream. Your idea would fit this kind of theme well.

If a couple sleep together, can one person having a bad dream cause the other person to have a disturbed sleep?

2 things I was thinking for your mod.

1st. dreams related to skills, maybe if the pawn works themselves to the learning limit for a skill in a day, they have a chance for a dream (I Built a tower to the moon, it was amazing) or a nightmare (I painted my friend, but it was actually a demon that came from the painting and attacked me!) about that skill, dreams giving skill experience/levels/passions where nightmares might cost them those things, to show reluctance to that skill caused by the nightmare.

2nd would be centered around loss, maybe a colonist suffering from a lost loved one could have a dream/nightmare about them, and get an associated moodlet from it, but it would also reduce the time on their vanilla "lost loved one" moodlet, since the dream or nightmare let them process their feelings.

EDIT: also, thank you for the mod and I look forward to the Eldritch direction you were talking about taking the mod.

1)Visions or "deja-vu" kind of dreams where pawns see something that could happen like death of a pet or recruitment of a prisoner with a moodlet like "wow I feel like I have seen that" or "I should have been more attentive".
2)Possibly you could even add a dream that leads to a quest like a dream where animals specialist finds a frienldly animal in danger and asks his fellow colonists to check a spot near the colony on the map or a psycaster senses dangerous raid approaching nearby
3)"Wet dreams" when colonists is missing his/her loved ones for too long like when a partner is on a caravan for several days or like he was hitting on someone but got rebuffed

A compatibility patch for the Sixth house mod where colonists with the dreamer trait are more likely to suffer disturbing dream events.

It could be really cool and unique if after a colonist dreams, they could have an aspiration or event to do something or recreate something from the dream and get a large mood bonus from recreating it outside the dream. Or maybe a memory that they had forgotten, and after recreating the scenario from the dream, they might remember it or a detail that they missed/didn't pay attention to when it happened outside the dream and get a large mood buff or even a trait from. Recreating it could work like the monument event like in Royalty.

What if there was a tiny chance for a fear mental break from seeing a sleep paralysis demon? You could even spawn in a scary looking pawn, even if just for visual effect.

I would like to see stats, traits and backgrounds play a bigger role in terms of what dream/nightmare colonists can get.

Examples:
Top human killer of the colony -> higher chance to get mass death/kill related dreams

The top insect killer -> higher chance to get insect-related nightmares

Bloodlust pawns -> predominantly dream of killing/butchering/blood etc. as a POSITIVE dream

Pawns incapable of violence -> dreams of killing someone is one of the most horrible nightmares they could get and should have a much greater penalty than on other pawns but be rarer

Cannibals having cannibalistic dreams is a positive for them.

I would also like to see rare mental breaks for certain nightmares (if they fail the roll).
So if they get one of the "terrorising" dreams they would have to roll against a Frightened/Panicked mental state and immediately wake up in that state, regardless of mood but it would not last long (configurable?).

If you get that lucid dream skill mechanic working using it to trigger inspirations could be fun.
Also maybe something to interact with the disturbed sleep debuff

"Remembered about the Burning of The Library of Alexandria: -400 (CE)"

Some kind psionic dreamer trait where they share dreams with other meaning if they have a good dream people near them get a good dream and vice versa

I don't know how much this would be outside the wheelhouse of this mod but! imagine if there was a special dream type for pawns with religions that have a venerated animal where that animal approaches them (or even dies, causing them to feel upset/lose faith/both) in a dream?

Based on my most recent dream: Traumatizing Dreams.
Litterally dreams so bad that they are remembered for a long time and can cause a pawn to have a major mental breakdown, or manipulate it's social relationships depending on who they saw in the dream. Can cause a minor mental breakdown on waking up. Can only be dreamt by one person at a time, min. once a month, and max. once two years because your colony will become wasted if it happens that all of your pawns go insane from those dreams.