SVG2 - expand the definiton for geometry properties

Hello,
this is my first message regarding the specification, and I'm not sure if
I'm doing this right but I have a a question/idea about SVG and I would
like to share it with you.

Why are Geometry Properties defined only on ‘circle’, ‘ellipse’, ‘rect’,
‘image’, ‘foreignObject’ and the ‘svg’ graphic elements?  Can geometry
properties be expended to include more graphic elements?

I noticed this inconsistency while working on a project that applies CSS
transitions on geometry properties of SVG graphic's elements'. Specifically
I was attempting to apply transitions on css-equivalent attributes 'x1',
'y1', 'x2' and 'y2' of 'line' element, however this can't be done since
geometry properties aren't defined for that element.

Thank you,
Filip Biterski