I don't think you need to measure having a better overall feeling. If someone says they feel poorly then they feel poorly. Suppose there was some object way to

I don't think you need to measure having a better overall feeling. If someone says they feel poorly then they feel poorly. Suppose there was some object way to measure such a thing, what are you going to do with that metric? Imagine being depressed and going to the doctor only for them to say, "no you're not, look at this metric!".