Here's another useful axiom:
"1 ounce on the tail adds 4 on the nose"
In other words, it's 4 or 5 times as important to lighten the tail. What pull cable are you using? Cabling directily to the horn brings up the abrasion issue, with the horn sawing back and forth on the cable with each control movement. I've been using a short threaded rod bent into an eye for the cable to alleviate that concern. I'd be happy to find a better way, though.
For that size airplane, a good weight saver is the Hitec 225 BB Mighty Mini servo. 2/3 the weight of a standard servo, and more torque.
The tailwheel is another place to lighten up.
Hope this helps!