From what I understand about the theory it has to do with human beings inate survival instincts - the same instincts found in all animals. The need to see and but not be seen (prospect and refuge), the need to find places where one can be hidden or hide while also see anything that might be approaching are aestheticaly pleasing. For example the edge of the woods or among the dunes or a high promitory.
The third aesthetic factor from what I understand are hazards. Which could be a rushing river or broken ground or the ocean or steep fall off or some unknown creature - physical features which are potenitially dangerous. The hazard are the reason for the need of prospect and refuge. Without the hazard to react against the stimulus is removed. Burke said 'that exposure to a sense of the power of nature, or better still to a sense of the infinite, was indispensable to the experience of the Sublime . . . , and this is simply stating, in eighteenth-century terms, that prospect symbolism and refuge symbolism also demand a hazard symbolism to make them work.' That is why steep cliffs, rushing rivers, the sea, and waterfalls are exhillirating there is certain inate danger involved which is quite pleasing to man.
There are a number of propects:
the panorama (wide view); interrupted panorama (imagination able to complete)
the vista (restricted by margins), usually defined by vertical boundaries; may be horizontal (under trees; from cave entrance)
secondary panorama (a vantage point elsewhere, potential view: tower, crag, horizon)
secondary vista: deflected (bend in river, curving trail in the woods, dogleg in the woods, pastoral view which disapears over the horizon), offset ( break in hedge)
There is certain mysterious appeal to the deflected vista, human nature wants to know what might be around the bend of the river or the trail in the woods or over the horizon of the hillside - stimulating that survival instinct and stimulating the imagination to create or fill in the image in our minds of what might lie beyond. All of these scenes are commonly found in landscape paintings throughout the centuries.
As far as the examples of green grass, blue water, flowerbeds, waterfalls and mature trees. They are not all universially aesthectically pleasing to all human beings - green grass or lawns are more developed western taste as are flowers. Blue water is pleasing (a hazard), but the wilder and more powerful the water the more aesthectially pleasing. A rushing stream or waterfall is more stimulating than a placid pond. And trees are aesthically pleasing as a form of refuge, but so too are pastoral settings and the most aesthetically stimulating is combination -- the house on the edge of the woods.
I do think there should be a ballance between aesthetics and golfing playibility, and utilizing natural features is good way of keeping that ballance. For example water can be aesthetically pleasing, but over use of water can result in boring golf - especially if the hazard is man-made and is of similar placid character.