Most ladies, and many men like myself have small wrists, so the "small" apple watch is already quite large compared to normal watches for most woman or men with small wrists. The "large" would over hang on many of those people, so you can only imagine how a 49mm would fit for most woman and people with thin wrists.

I had always heard that the regular Apple Watch was one of the smaller (smallest?) smart watches out there. Is that not the case?

Even in the Apple keynote demo videos, one of the female models had a tiny wrist with a giant watch on it. Not the most stylish look.

As a small-wristed male, I would also love a thin watch, without a lot of the sensors.

Yes, I'd be happy with even just the the extra side button to start workouts and such, since whenever I put on the homescreen it mistakenly gets started when crossing my arms or such and gets pressed. I imagine that may eventually come to the regular models.