There is a multiverse with different settings in each of its universes - steampunk in universe A, fantasy in universe B, biopunk in universe C, etc. And in steampunk world there is a group of characters who are suffering from insomnia for different reasons.
Character 1 - Female, "Rogue" (basically, a gunslinger and a swordfighter for hire). The body she currently considers to be "hers" is in steampunk world, although in truth steampunk-body is merely her "avatar". Her real body is in cyberpunk world and it is sustained in medically induced coma due to medical experiment. When her steampunk-body goes to sleep, she awakens in her cyberpunk-body, which is quite unpleasant because:
- her cyberpunk-body is kept in a really small medical capsule (like a coffin, but even smaller);
- her comatose body can't move much;
- she is claustrophobic;
- all her memories about cyberpunk world are locked, she considers steampunk world to be a real one and cyberpunk-one a nightmare (although all of them are equally real).
tl;dr: she suffers from nightmares, therefore she strives to sleep as rarely as possible.
Character 2 - Male, "Doctor" (or "Flesh sculptor" as he calls himself - basically, a mix between a surgeon and a necromancer). Came into steampunk world from fantasy one by accident - he was asked to bring something from lower levels of basement in the medical university he was studying in, got lost, stumbled upon a secret passage which led to even deeper dungeons... Long story short, he somehow ended up in steampunk world with no knowledge of how to get back. Back at his world education is rather unusual: students don't have to waste hundreds of hours on studying books and manuals because all of the information they'll need gets telepathically written in their heads. However, nobody would be able to stay sane after getting this huge unstructured chunk of information, so all of this knowledge is locked away. As students keep practicing and understanding things they already know, knowledge gets unlocked bit by bit while they sleep. It's not a pleasant way of learning (day and night, literally), but it's really effective. He follows Rogue (because there is nowhere to go for him in this alien and quite weird world) and stitches her up (both figuratively and literally) which gives him a lot of practice and a lot of "learning nights".
tl;dr: he suffers from constant headaches caused by sleeping, therefore he strives to sleep as rarely as possible.
Character 3 - Female, "Huntress" from the biopunkish world of polymorphs (i.e. human-like race who can reshape their body at will). Although this race prioritized everything related to their unique biological abilities, they managed to create a dimensional gates and travel to other worlds. They weren't careful enough with destination of these travels, which lead to technogeneous calamity on their planet: their civilization was almost completely destroyed by uncontrollable grey goo they call "Corruption". The grey goo consumed most of the planet's surface and went dormant for no apparent reason. So now they have to find a way to get rid of this grey goo without waking it up AND (preferably) getting back everything it ate. That's where dimensional gates came up again (if this goo came from somewhere, there has to be a way to find its creators, right?) The "Huntress" was one of the agents sent through the gates to find a solution. For obvious reasons all of the agents have to work very carefully, without disclosing their nature or fragile state of their homeworld. This, plus constant stress, plus "fate of the world on your shoulders" would make quite a lot of these agents very paranoid.
tl'dr: she suffers from severe paranoia, therefore she strives to sleep as rarely as possible.
My question is: how plausible are these explanations for insomnia?