What's My Next Novel?

So here I am sitting comfortably between the completion of Novel Number Three and the beginning of Novel Number Four. Usually, by the time I've finished one project, a handful of others, which have been burbling for months in the Mind Swamp, start to compete for my attention.But the Mind Swamp is strangely quiet these days. Not an idea fish in sight. It's both exhilarating and a little bit terrifying.I've spent the past few days brainstorming. Just throwing stuff out there. Seeing what sticks. So far, lots of throwing, not so much sticking. Here's an abbreviated list of ideas I came up with and quickly discredited.1. A Jail Storypros: taut, claustrophobic tensioncons: never been to jail, possibly depressing2. A Mind Swap or Bodysnatchers Storypros: creepy, sci fi, potentially sexycons: been done, most recently by me3. Retrofitting My Unpublished Space Opera Into an Urban Fantasypros: characters, plot are already developed; urban fantasy cool right nowcons: what to do with all the space ships4. Jesus Christ, the Teen Yearspros: ?cons: offending nearly everyoneKeep in mind, these were the best ideas. I think it's back to the drawing board.