Clearaudio emotions turntable ???

I assume you're referring to the single-set screw design? Or is this an arm-geometry query?

I would like a more secure mount for the arm on this table but after 3 months I haven't found the single screw to be a problem. Still, more would be nicer.

That and how they go about setting the proper height.
The directions say to use the three "flat pads"... by doing this the one rca connector is inaccessable.

Why not put a shoulder on the mounting sleeve?
Or make it so three dowels, evenly spaced on the diameter, fit into a mating surface on the base? This would establish height, maintain the arm assembly square to the base and fix the orientation. Then use the set screw.
The Germans got lazy with this design.

If I remember correctly though, the "shims" technique is only used in the instructions when first assembling the table. Once you're ready to align the cartridge you'll need to adjust the arm height (VTA) and that RCA become accessible again.