What type of books are your most technically challenging to write?
I'm wondering, what would you consider to be your most technically challenging books to write? IE, what are the ones you work the hardest on in order to create an interesting story and keep it that way throughout the book? IE, keep the reader hooked all the way through. I think mine would have to be the more methodical, slower paced books. I can do action, adventure, drama, space opera, and anything a mixture of strong action and mystery/intrigue. Going between the intrigue and the action for me is easy. It's also a good way to break up a book to keep the reader interested without subjecting them to action burnout.
But when you're dealing with mostly light drama and suspense with very little action, generally I struggle at that. My current novel seems to be that way. I ended up 2/3rds of the way through the story before I hit any action, and that was very brief. The rest of it is held together with drama and suspense. So far that's proving to be tough for me to do and still keep it together without the benefits of some action to keep things stirred up.
What about you guys? What's your most technically challenging thing to write?