You've got the top view of the hull in good shape. Now, it's time to work on the shape as seen from the side. Check the following steps:
Press 1 on the NumPad to get the Front view.
Notice that the hull is still oval shaped. As seen on the left of the next screenshot, the top is not flat.
Check that all the control points are level vertically. All of the upper points should be at the same height in Z. All of the lower points should be at the same height in Z. If any control point is higher or lower than what it should be, you can select it and scale it in Z, or move the vertices in Z.
Press Ctrl + R to activate the Loop Cut tool. Select the horizontal magenta line.
Move the orange line until it is almost ...
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month, and much more.