Sketch Model 1
Issues with this sketch model includes placing the D in the centre mark, and the placement of the SD being a little awkward.
Sketch Model 1 Revised
Sketch Model 2
Sketch Model 2 needed improvement in how the D,SD and SO interacts and it is very cluttered. The D is also not clear and needs to be larger.
Sketch Model 2 Revised
The sketch model became more dynamic by extending the D and placing it in an ascending height. It contrasts nicely with the interaction of S, SD and SO.