The Insect Strings I've been talking about here are "springy", which is one of the things I love about them. They are .009" diameter, slightly thinner than an E guitar string, which is .01". The size is virtually the same but the insect pin flexes. I can move an installed antenna a good half inch and it springs back to where it was. Using a tube for a sectional antenna will reduce the effective flex, I'm sure. I am trying this so should have something to say later.
I know some object to the ball end but they can be cut off and another method used for the ball. Personally, I like how the insect pin ball relates to scale and looks good to my eye.
I like the look of your bases ... are they metal? The rubber grommets look great.