On the FAQ it states the rate of lifetime happiness is 1 per second while happy. Do positive moodlets have any usefulness above what's necessary to be elated?
Elsewhere on the guide the over-emotional trait is often recommended, and the big mood gains possible with the spa Packages. However, keeping my sim's needs met plus one or two common moodlets (such as well rested and clean clothes) usually keep the sim elated. What benefits are provided by moodlets if already elated?