Please do make this. I am big fan of this kind of switch. I use https://www.amazon.com/GE-Occupancy-Required-SmartThings-26933/dp/B071Y38FX5/ for this, or non z-wave Amazon.com
I personally think the GE switches look fine and the sensor is there, but yes, it doesn’t look like a normal light switch.
Also out of the dumb occupancy/ vacancy switches, I have liked the luton for cosmetics and function.
Both function great. I use them in walk in closets, and half baths, or toilet room. When you walk in, the light turns on. After a minute, the light turns off. The small spaces it works great cause it doesn’t shut off when you are in the room. I don’t use them in Full baths, I think if someone is showering and, or bathing, it may not be able to detect motion and like you mentioned waving arms around is kind of silly.
I also have them for my stair wells. I feel like my hands are always full going down to the basement, but upstair stairs, I added light/outlet receptacles instead.
I like the z-wave part so that after 8 PM if I walk into the toilet room in the master bath, the light comes, on, but only to 5-10% and during the day it turns on to 100%
New home I am moving into, I will be putting in 7ish of these switches of a virally of flavors TBD.
I also use z-wave motion sensors to activate regular z-wave switches. This works great 98% of the time. I do this when the switch location doesn’t fit the area I am checking for motion, or if I need to have more than one sensor for a single switch.