My strategy for washing is to remove the greasy, gritty dirt first, then wash the least dirty parts and lastly, the parts that were greasy and gritty get a final wash with soap and water.
My bikes don't get ever get a lot of dirt on them. The parts that actually get somewhat filthy are the underparts, the belly pan, the LH underside of the tail from chain fling, the wheels and to some degree the very bottom of the lower fairings especially the chin which seems to get a deposit of tar or rubber off my front tire. I first remove the grit and grime from these areas with paper towel and WD-40 before actually washing the bike with soap and water and a microfiber towel. If the underparts get some swirls that's unavoidable and it's better confined to the underparts.
The top parts usually are pretty clean so I start there with a car wash/water solution. I try to avoid drenching water into the electronics and under the seams in the fairings but I slosh the soapy water on so the dust is rinsed off rather than needing to be rubbed off. A spray of bug and tar remover works very well to soften up those bugs that get smashed on the upper fairing and fender so that I don't need to rub on them to remove them. A second spray of bug and tar remover and wash is often necessary to get every last bit of bugs off. The lower parts of the fairings are the last to get washed. I then wash the wheels in the same manner but I squirt a wheel cleaner directly on them first being careful to avoid getting the soap into the brake pads. I usually wash the swingarm brake calipers and fork bottoms at the same time as the wheels. Then a rinse with fresh water, same order as the wash, start at the top, bottom last.
I only give a bike a real soap and water bath about 3 times each year and I usually follow that up with a polish using ICE paste polish. In between washes, I clean the bikes with spray detailer but as mentioned, that usually requires some rinsing with water first but not a total bath. Plexus does have an extra shine and slipperyness to it but I've heard it leaves behind an actual film that might not be desirable if you want to repaint the surface.
What I find remarkable is that the clear plastic on my windscreens and helmet face shields never have gotten the slightest swirl. They look absolutely brand new after 10 years. Plexiglass for windows in a home scratches very easily but not windscreens.