The method of construction used in Jones Guitars, are that the sides are slotted into the neck as a whole unit, rather than the neck being applied after the body has been constructed.
This is a more cumbersome way of construction, but the neck is not overally dependant on a glue joint in one of the most stressful areas of the guitar.
An area where sound transmission can be increased, is the location of the bridge, a larger area of mass covering the sound board at this point, but not too much to restrict the soundboard, can increase volume & clarity as the vibrations of sound are amplified through the guitar. This is particularly noticeable on softer spruce tops as compared to stiff brittle spruce tops.
The mass of the bridge is dependant on the stiffness & tone of the sound board on each guitar. If all woods were perfectly uniform in composition, then maybe guitar making could become an exact science, but thank god its not, so people like myself can experiment on ways to blend timbers, ideas & experience together to create a unique instrument for someone to express their own creativity.