Pure sand is silicon oxide [ or dioxide] and is very resistant to decay and has VERY little plant food material. You will need to bring in organic matter and likely fertilization too. Those sand 'hills' you make wash down. Duh...no easy answer here.

i may have to give up, or plant water lillies :)
arrggg....
every year it wipes out seedlings

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My suggestion is a lot of mulch to protect the seedlings and maybe a french drain to carry the water to the street.
This year I got two free truckloads of shredded wood from a tree company. It covers the ground and paths so the dogs don't get muddy and it is good mulch, I just add a little nitrogen to the garden.

Build raised beds with rigid sides to retain the soil.

I see a lot of uncovered bare soil, that alone leads to erosion, low microbe activity, water pooling, etc. I also see whole leaves, which tend to form a mat, smothering the soil. It doesnt allow the best air flow to the topsoil. On the other hand, if you take those leaves, shred them up, and mulch your garden thickly. I would even mulch that pool you have.. Put enough mulch to absorb the excess water pooling after rains. Not only will mulch absorb the excess water, it will make a favorable habitat for microrganism activy, which is the true key to soil stricture,function,etc. Keep adding more mulch(prgnaic matter) as it gets eroded away. Try to grow cover crops and keep the soil covered/protected at all times, all things you would do to prevent the erosion you are talking about. Eventually the microbs will get build soil structure and less pooling.

Well i wish i had before pics.
there actually was a lot of mulch and organic material in that soil. i had added it a month before i planted, but after several rains, the ground becomes so saturated anything organic comes to the top, then just washes away. It collects in the lower areas, becoming very an-aerobic since low areas take many days/weeks for it to dry out.

It reminds me of putting soil in a glass with water, shaking it vigorously, then waiting.
The heavier sand will go to the bottom, everything very light is at the top, and that gets washed away to lower areas.
The puddle is actually a walkway,

Last August we had 6 inches of rain in one day
A couple of years ago we had 27 inches in a month.

i had added the leaves to try and protect the mounds from washing away when i knew another round of heavy rains were coming... i built them about a month ago, prepping the area to plant papaya and other fruit trees.
I may just have to cover them in plastic and make holes for watering ? Any place the soil is bare it turns to sand.

The only thing that seemed to help is adding heavy sand in with the compost to try and keep it down, or something on top that wont wash or blow away.

A drain is the solution, but too expensive, the street is 80+ft away, and i cant dig that much with my back.
I am thinking heavy mulch on top, then adding pea-gravel on top of that to keep it in place. i may have to use extra N, but i can do that.