I don't remember the exact word count, but my thesis ended up being approximately fifty pages. It evolved out of a short story I wrote in a second-year Creative Writing class. Basically, the piece charts an unlikely friendship between two individuals who meet in Toronto during the summer: a twenty-something, drag-obsessed transgendered student who has stopped speaking to his mother and a thirty-something, laid-off professional who has recently separated from her husband over the death of their child. There's lots of heavy stuff going on there, but the tone is also relatively light.
Why was the required length of your thesis reduced? I imagine to accommodate your graders? Hopefully it's still long enough that you can produce something substantial and satisfying.