I am using sub groups within components to make dynamic components resize without distortion. I have lines and faces hidden on section views so they don’t show.
With Merge Border on the licensed version, you can make the border disappear using toggled tagged geometry or hidden geometry.
You can also get rid of the lines manually - right click on the curic section face, unlock it and hide the unwanted lines. But the lines would reappear if you generate the curic section again.