That is a good looking console, where does it come from?
Is your transom not a bit "thin", just asking don't know the calculations myself but your putting a lot of weight and power in there.
I don't know much about the 666 but the hull looks like it will make a great stable fishing platform and will have a very shallow draft. The keel strips are very wide and flat and as you say the tunnel wide and square.
The boat itself is big as it is almost 2.5m wide and 6.615 long. I have set the transom at 610mm but the gunnels are about 1000mm. I also like the large square nose as it makes a great casting platform and looks like it will divert wake away from the boat when on the plane when the wind blows. It is very solid and a great hull for the application I am going to use it for.
Please explain what you mean it should sit open at the back