Ok so this is kind of a confusing request (hence the confusing title) but bear with me,
currently, you can create an object and add a border radius:
and create a circle like this:
and a rounded rectangle by stretching the shape:
BUT, and this is both important and unnecessary, you can’t enlarge the border radius and have that create an oval like shape:
I think this is to do with the way that CSS deals with border radii but it feels like it is more intuitive to allow it 
Arthur
