You need a bit of “asymmetrical balance” – to achieve it, disparate things (including negative space – it all counts) need to be balanced vertically and horizontally. Your horizon is at the vertical midpoint and the boat at the horizontal midpoint, which is symmetrically balanced (it’s the asymmetry that normally adds the interest) and the weightier subject is in the lower left quadrant, throwing the balance way off.
If you crop to roughly 3/4 of the width and height, taking away from the top and right of the frame, you’ll have better asymmetrical balance.
There’s no righteous rule of asymmetrical balance that you have to adhere to, but it’s a principle which does play a part in building a pleasing image.