I am also planning to create a windwept Boulevard Cypress. What I am going to (probably) differ is;
- Remove most of the branches (or maybe all) on the side facing the wind (lefthand side in your case), especially the thick ones on the lower part of the trunk. I guess it is better that branches do not cross the trunk on the lower midsection of the trunk. Plus, I guess branches at the side of the trunk facing the wind should not be strong.
- Make the trunk more slunting to the direction of the movement and bend the upper portion of the trunk more so that apex is nearly parallel to the windswept branches.
- Remove some of the windswept branches as well, maybe create a jin, since the foliage of the tree looks a bit messy. I guess it will be better to give a bare, worn out look to achieve an image of a tree grown in difficult conditions.
- Add more movement to the windswept branches as well, a waving movement rather than a straight line.
- All windswept side branches, the jin, the apex and one or two very thin and short branches on the side of the trunk facing the wind will be parallel.
These are my 2 cents of course, I am not a design expert!