While recognizing that this thread has, due to me, drifted off-topic, but, well, with your forbearance please.

In July 2024 I tried a watercolour brush in the Affinity Designer software program, looking at how overlapping brush strokes look.
Well, rather than just arbitrary brush strokes I decided to try to sort of sketch a seascape of the tide coming in over a beach, thus sky, sea, sand.
Using only one colour for each, so three colours in total.
The result seems to have more than three colours,but that is due to the overlapping of the brush strokes.
I started with an A2 landscape canvas, then I added an A3 plus bleed areas rectangle in the centre.
First I did the sky, then the sand, then the sea. This order as I wanted to try to have the effect of the sand being visible through the water of the incoming tide where the leading part of the water was not very deep.
So most overlapping of brush strokes of sky upon sky, sand upon sand, sea upon sea, yet some sea upon sand.
As it happened, rather than just leave the result as an electronic image, I made a copy of the Affinity Designer file and in that copy I enlarged the guide rectangle a little to become double the size, both horizontally and vertically, of the size needed for A5 plus bleed areas, then exported that selection at exactly half size as a png (Portable Network Graphics) graphics file, using measurement in units of pixels for maximum accuracy. I bought a giclée print and framed it.
Until yesterday, I had been thinking that I should have put the horizon across the middle of the picture. But after reading (part thus far) of the book to which John kindly supplied a link, I now realize that it is good that I had not put the horizon across the middle.
So, bearing in mind that I am a beginner and how the picture came to exist, I am wondering what is good and what is not so good about its composition.
Is the horizon in the right place?
If not, where would it be better placed?
Is the sea and sand "quasi-horizon" where the sea meets the visible sand in the right place? I have sometimes thought it is too high up the picture, but it is an incoming tide, not the tide already in.
The illustration is approximately half in both directions of the A5 plus bleed areas png graphic, so around A7 in size.
William