Gods of Strife (my last completed novel that is now at my publisher) had a first draft that was about 77,000 words and the final version ended up being 88,000 words or 11,000 words longer (another 14.3% longer). So the current WIP will, after re-writes, edits, and proofreading end up being over 60,000 words easily.
The problem is NaNoWriMo. I pledged to write 30,000 words and I'm part of a group that is counting on me to put out a bunch of words. And yes, I've written 17,274 words so far in November (including 160 words today on slight revisions to the WIP I made this morning) which is over half my goal of 30,000 words and not a bad start on 50,000 words, I pretty much have nothing to write about to get the remaining 12,726 words needed to reach 30,000 (32,726 to reach 50,000). Yes, I'm ahead of the curve (I've written 10 days worth of NaNoWriMo writing rate in less than 4 days) but I HAVE NOTHING MORE TO WRITE.
In a week or so I can start doing revisions and re-writes on my WIP, but that's slow and doesn't add a lot of words very quickly. If I could come up with an idea for a novella or something else to write, maybe I could reach at least 30,000 words. I don't know. I am, unfortunately, not a writer who can write on demand. I need to have a good idea at least to start with.
So my first attempt at NaNoWriMo maybe be a crash and burn. But mostly because I had my WIP nearly finished by November 1st.
Oh, and the WIP is called The Black Hole Treasure (although I may change that to Treasure of the Black Hole) and is a hard-boiled private detective about 5,000 years in the future. Sort of a "Sam Spade in Space."