Hand in Hand Mechanical Pendulum Clock

I ran across this hand-in-hand clock design http://www.instructables.com/id/Hand-In-Hand-Skeleton-Clock/, and I thought it would be more fun as a purely mechanical mechanism. My model uses a 15 tooth, Graham-style escapement and a 480g drive weight. Shafts are 2mm save the two bottom ones which are 3mm. The pendulum is a 6mm aluminum tube that may be adjusted up and down in its mount. It has not stopped on me yet when I've had it running, though accuracy is not the greatest.

Though it works very smoothly at present, the clock is still a work in progress. It requires the following improvements:
- The sprag clutch system that serves as the drum is too stiff. I had to play around with the sprag sizes to find something that marginally works. Re-sizing the wells in the inner drum might allow for 4mm delrin spheres which should improve performance.
- The back frame ought to be augmented. At present it must be mounted to a board or held in place with my hand (as in the pictures