Measuring for the sake of measuring isn't useful. Burnout may have become a catch-all term but it isn't meaningless, it means that the person is currently fatigued and action is required. It matters that the root cause is identified, it could be a health issue, an environmental issue or more probably a combination of factors. The KPIs you set as I see are arbitrarily chosen, not sure what you are measuring or why and can't even say that the goals are SMART (specific, measurable, achievable, realistic, time-sensitive).