Importance of the first three Brahmaviharas in Theravadan Buddhism

So while reading a lot of teachings, especially "higher" teachings, a great deal is mentioned about dispassion in worldy things, unattractiveness in the body and various contemplations on death. It's quite easy to get lost in these kind of contemplations without developing the Brahmaviharas to feel something positive (especially social positive emotions are important for humans). I'm wondering if positivity is highly stressed in Buddhism? On the one hand the brahmaviharas are not withot reason called "the divine **abidings**". So I think one needs to dwell in them as much as possible. Also the last two points of Right Effort stress the importance of cultivating and maintaing positive emotions. On the other hand though, being non-delighted in things makes this look rather grim. Maybe I haven't read much Suttas on Compassion, loving kindness, generosity etc..