Whatever the design, I like a clavichord that allows a wide range of effects. One can play the clavichord like a harpsichordist, mainly in terms of articulation and the basic tonal clarity. But what I think fascinated the players of bygone times was the incredible variety of expression allowed by the natural clarity combined with many variations of dynamics and color. Those ecstatic descriptions we have from the later eighteenth century seem to suggest that kind of quality and there's no other instrument that can provide it. Models from the early eighteenth century and before can have this quality as well, of course.
Some clavichords only resonate well in the middle of their ostensible dynamic range.
Naturally, carrying power is more important than volume. It filled a large, crowded room and carried all the way to the back, I'm told. Certainly it sounded loud and full up close, but it had such integrity to the sound that it reached out very well. That is what is important. I like the J.H. Silbermann, Friederici, and Hoffmann unfretted designs.