On the issue of slop with Z-bends: I don't drill out the servo holes. Instead, I sharpen the end of the push rod, and kind of twist it into the servo hole so it's nice and tight.

I do recommend ez-connectors for throttle, but even there you have to check them occassionally. Last time I was out flying I lost throttle control because an EZ connector came loose. Do you know how long a .46 will run half-throttle on 8 oz of fuel?

Personally, for the control surfaces, I've settled on a Z-bend at the servo end, and a high-quality screw on clevis at the control surface.