It was the different radius on each side that grabbed my attention, made me wonder was the transom supposed to be straight across!
Nothing to worry about then?
The Delta has a deep V hull so a long shaft engine sit quite low on the hull and can be swamped by a stern wave if you stop quick in a straight line. The solution is don't stop quickly or reverse into waves, or fit a skirt to the inside of the transom. Delta did a GRP moulding for this.