It took about 5 seconds to get my pulse while not exercising. It does not continually take a pulse unless you are in an activity mode which should be just fine for the majority of people. I'm not sure why your wife would have needed 3 apps for to use it but I guess she has some reason.
I don't put much stock in rumors regarding Apple. I suppose the sensor for heart rate and the gyro could be used for monitoring sleep as poorly as any other device on the market but once they announced the 18 hour battery life any reasonable person would know that it wouldn't be useful for sleep monitoring. But as I said no other device currently out is really very good at doing such although they claim to be.
For most people the sensors on the Watch and the apps will be more than enough (I realize it won't really work as well for Crossfit enthusiasts). My only point was you purchased an item to perform an act that it was already known it didn't do. Sort of like buying a Ferrari and complaining it doesn't get the same gas mileage as an Accord. You are comparing a wearable smart device and watch to something specifically designed for one use.
I doubt Apple wants to steal anything from Fitbit at this time since they are being sued for stealing their technology from Jawbone.