My opinion page addressing inquiries concerning clawhammer technique.
When playing in 3/4 time, try using "brush skips" in place of one of the two "brush thumbs" in each measure. This will soften the sound in such a way as to make waltz tunes easier on the ear. Look over some of the 3/4 time tunes on my tab page and you'll get a feel for this "softer" approach.

Thanks... Mike