Given the slightly Diapason-like tone of the 8' GO Flute of the Rieti organ, I felt it would work well for a repentant Bach chorale-prelude. Here used with GO Montre and Ped 16' Flute, with the very slow-beating Tremblant Doux.
Rather than soloing out the melody, I often find it a nice voicing option to instead simply bring out the top note of the part to vary the texture. I'm seeing how slow to take the tempo without it becoming a trudge. Not sure if successful..