Slow is a tempo, nothing more

I had a first read-though of my sixth quartet and discovered a major mistake. In-between two very cheerful movements at a quick tempo, I had sandwiched a slow movement that did everything slow movements are supposed to do, except be the right slow movement for this piece. With lamento gestures, pithy points of imitation, and swelling chromaticism, the effect was one of cinematic melancholy, schmaltzy enough to spread across the bread slices of a hundred Hungarian kindergarden children just waking from their afternoon naps.

The task now is to find another slow movement, slow in tempo, but of a piece with, or making a meaningful contrast to, the sunniness of the outer movements.