I absolutely adore the Loves the Outdoors trait (from TS3). It's a guaranteed +20 moodlet whenever a sim is outside, and it supposedly makes sims better at fishing and gardening, two skills I enjoy very much. At the very least, they'll automatically be in a better mood while building their skills. I also tend to give the trait to other self-employed sims, like artists or sculptors, and put the easel or sculpting station on the porch. If you add the outdoors boost to "having a blast," at least a "nicely decorated" moodlet, and a boosted stereo blasting their favorite music, their moods are already maxed out before they do anything else. And I always like seeing my sims happy.