Cliffhangers, mysteries, twists, and questions

I'm rewriting my riddle quest novel, and I'm noticing the chapter ends especially, and their variety.  We're often urged to end chapters with a cliffhanger, leaving the reader dangling in suspense, but we can't do that for every chapter.  If we did, the pace of the story wouldn't vary, and we'd be leaving the reader feeling breathless by the time they reached the end of the book.

We need variation in chapter ends as much as we do in our novel's pace. But that doesn't mean we can end chapters like damp squibs.  Even though we might be ending a reflective or slower-paced chapter, it still needs a decisive ending.  This is where alternative endings come in: mysteries suggested, revelations, unexpected twists, or the posing of a new question for the characters.

One writer who uses these alternative endings brilliantly is Martha Wells in her Murderbot Diaries novellas.  Murderbot is the main character, so we expect it to survive to the end of the story.  But when it is taken over by hostile software and needs to block that download, it chooses an unexpected solution: "so I grabbed the handweapon lying on the seat, turned it towards my chest, and pulled the trigger."  That's totally unexpected, and also a brilliant cliffhanger.  Murderbot, of course, survives.  It's a half-organic, half-mechanical construct, and as we then find out, it can survive situations that would kill humans.

In my novel I have a cliffhanger where one main character has a knife held at his throat, and the antagonist is telling him he's outlived his usefulness.  I have another cliffhanger later on where he's  traversing a slippery ledge to a cave behind a waterfall and his foot slips off the ledge.

Then there are the twists.  My other main character is dealing with the sudden death of her mother.  She discovers her mother was investigating riddles engraved in an alien script on a gold necklace.  The twist is that my character wasn't told about it.  And when she finds out she realises the consequences of the antagonist finding the answer to the riddles first would be the death of her family.  So she has to go on a quest to find every object th riddles refer to, and this provides the narrative structure for the novel.

I've got cliffhangers, mysteries, twists and questions in my chapter ends, and I think they're working well to keep the reader engaged with the story.