Tom Loose, a prolific K-Factor contributor is full of ideas. I've built some of his "EMMs" (Elevator Moving Mechanisms) out of 3/32 music wire, aluminum block and scrap wood. They slide effortlessly back and forth. Resistance increases when a significant side load is applied (elevator differential). The one in the center is 1 inch wide and has the least slop. I tapped the front with a 4-40 thread to attach a CF pushrod. The tops are tapped with 2-56 to hold the dual CF elevator actuator. These will fit in an Aries or Entropy. I am somewhat concerned about rust, but some lithium grease so far has kept them moving fine. If you know how to stop rust, let me know (Lance).
I built up an Aries rudder to see if it saved any weight. It took about 1-1/2 hours to build. The majority of the weight, it turns out is in the leading edge and end caps. This only saved 6 grams. Not worth it.
Here are 2 alternative ways to shape your stab:
(above) This is the standard Aries stab as shown on the plans
(above) This is an alternate Aries stab I am building to see if the larger elevator and counterbalanced ends would allow the plane to perform 3-D and precision aerobatics. I found that the counterbalances negatively affected slow speed flight. The Aries has excellent slow speed characteristics (the best I've flown) and these seemed to remove precision. No noticeable effect at higher speeds.