Three positions: in the middle, a little off-centre, and close to the edge.
It can be that my point is rather big for this exercise…
The first image is working well, according to my opinion. The diagonal lines help to break the static impression and the shape of the object seems to be pointing another diagonal line.
In the second image, the point is place a little off-centre is is still working again because of the diagonal line the point is creating in the image, dividing it in two parts. The image is equally divided in two parts.
I believe that the third one is not working. There is no particular reason in the situation to have the point so close to the edge and the image lucks interest.