I usually do a lattice back brace pattern on most of my guitar models including the Penelope. For this nylon cross over I decided to use the more standard latter braced style.
I get a wonderful amount of bass with the lattice style braces. With nylon strings it's not the bass you need to worry about to get good tonal balance it's the highs and the high mids. Ladder braces are stronger in that area.
On the go bar deck gluing on the back braces: