Now I have reached about as far as I was when I decided to switch to this more compact size and form factor. So plus-minus zero in progress now, so to speak.
One out of six rods with Igus plastic rod ends, done. Five more to go. The little medallion/pendant shaped thing on the right is a lid for the hole where the Z-spring anchor sits from below, so it doesn't fall out or bind when not under load. It will be held in place with a tiny M2 screw I salvaged from a dead laptop prior to this project. Scavenging parts has its uses sometimes.
Here is a closer look at the z-spring anchor point on the under side of the base. It's a little hard to see because the aluminium glares and reflects all ambient light so all edges are a little blurred. In addition to the hole for the swivelling Z-anchor part I also milled out a trench around it and made it into a tear-drop shape. You'll notice that the edges of the lid will fit in that pocket but also seal the z-anchor cavity by covering the outer edges of that "chimney" shaped inner wall. When the lid is screwed down with that tiny M2 screw the Z-anchor part will not fall out.
Yeah yeah, I know all the screws are of different types and look a little rusty. I took what I could find in my screw and nut parts box. Oh, those are sized down to M3 now, to fit better on the now smaller base. So I have no M4 screws at all in this build now.