You're right, that was Inventor Fusion. In 360, I'm not getting dimensions to show up when creating an ellipse, but I am able to add dimensions after creating an ellipse. Going back to your workflow, it looks like those instructions will create a stepped object rather than a smooth object. After extruding the ellipse, it doesn't look like I can add dimensions to the extruded surface (dimension tool isn't availabel for this purpose—it's grayed out) to taper the shape. I can only create a new shape on the surface, add dimensions and extrude it. Any suggestions?
Sorry, I didn't realize you needed to include the transitions.
Have you tried to loft the shape and then slice it up?
After you loft all the sketched profiles use these offset planes that you created for the loft profiles as tools for Modify > Split body.
I thought of one more option:
Sketch the profiles on the stack of offset planes
Make one loft per body between each successive stack part and the next sketch in line.
Use Continuity > Free to keep the sides as a straight bevel shape, instead of curving.
I realized that my previous pictures show curved edges on the sections which may not work well in a CNC router setup.