Well... I think that couples who are firm in their relationship, who have solid trust and foundations - do actually make happier couples.
Why? Because they're/we're more liberated, more comfortable in our own skin, know what we want/don't want in life and know what we want from swinging as a couple.
I think it makes the bond stronger and makes things overall just more relaxed and at ease. Which in turn makes people happier with their lives. Instead of the grind of daily life.
Of course, talking after meets and being a couple again, or talking and the lead up to a meet, heats things up in the relationship anyway and usually you can't keep your hands off each other. This extra intensity leads to increased bedroom activities and makes normal couples into raving perves who think about not only when they can next have each other, but where and possibly with whom.