Best way to render lines and circles with (or without) collision?

I am working on a project that needs to display and interact with basic geometry: Lines, and Circles.

I have been trying for weeks to determine how best to do this in UE4 and have yet to find a solution. The FMath functions have all the functionality I could ever need, but I need to display the geometry as if I was in a Matlab visualization.

I tried using Cable Components as lines and while they look good, they do not have collision on them - which forced me to build a very clunky system to detect overlaps. I also tried using spline meshes as lines, but they seem to deform in unexpected ways.

I was able to build perfect circles using splines, but when I applied spline meshes to those splines, they always deformed in less-than-perfect ways.

I need the lines and circles to be able to be scalable at runtime.
Any advice would be appreciated.