Currently the addon produces a lot more geometry than is necessary. Calculating beautiful lines while avoiding z fighting, with varying widths is not a trivial task.

Consider the picture below. All the circular parts you see are starting and end points of a continuous print line. 2 have been marked with arrows for better clarification.

Ideally, this should all be one print line. With one circular start and one circular end. That will require a boolean union algorithm that currently only exists in my head. It will be the biggest new feature. It can reduce render times by maybe 30-50%. It will open the doors for a lot of other cool features like single layer animations.