Add points to drawing/recognize more arcs?

Is there any way to add points to the drawings? I believe it is due to the organic shape of my object, but most of the points I can select aren’t at places I need to measure. I want to add points along certain lines like so.

On the arcs/circles, I can only select the diameter for perfect circles? I have no option to do anything with most of the arcs on my object.

The drawing mode in shapr is so streamlined it’s a bit disappointing that it only seems to work on perfect shapes. Thinking I’ll have to take this into rhino.

Is there a way to get around this?