I like the Lines2Tubes.rb plugin, for quick rendering, but prefer the tubes to be copies of a "master" tube component.

With the master tube-component axes aligned to the model-space axes, I can scale different tubes to custom lengths. To make all the tubes fatter or thinner, I simply modify the "contents" of the master component, editing in its context.

(...BUT, it requires a LOT more effort!)

Now, if I could only have the "best of both worlds."

Case in point...
Taff