I decided it's probably time to explore way down into the weeds, spinning out my detailed thoughts about all the possibilities of each individual element. Maybe I'll interleaf these posts with the thread I've started on choreo, just for a bit of variety.
When you are coming up to speed through the beginning levels of skating, most of your initial lessons are for moves you will later grow out of, and never perform again once you're a serious competitor. A couple of the early moves though are suave enough that you actually can use them in your mature programs, with just a bit of polish and embellishment. One of these is the scratch spin.
I don't see this much mid-program -- it must be terribly disorienting to exit a scratch spin and proceed to your next element. Maybe once or twice in a competition though I'll see a gal end her program on a scratch spin, and when done to perfection it's an arresting finish. The risk: it is easy to blemish the spin when you're tired, and if you get remotely dizzy you'll fall out of your final pose.
I like to see unexpected entrances to the scratch spin. Sometimes a gal will enter it standing from a sit or a camel spin. Sometimes you'll get a nice three-turn entry. I like to see the speed anticipation build up in a slow straight perfectly gradual progression: as your off-ice thigh gradually lowers and your arms curl in, it's fun to watch your revolutions quicken. Of course I want to see your contact foot in such a tight non-precessed circle that you're pretty much drilling a hole into the ice. If I'm fortunate enough to be alone with you in a freestyle I want to hear the smoothly louder swashily as the blade reaches resonance.
I want you to get so fast you become a blur.
Arms and hands should have some planned sensibility to them -- I've seen scratch spins with one hand in front and one in back, with fingers gently suggestive (maybe a two finger scout salute). Also nice is if you can do fancy positioning higher up near your face or overhead -- of course the higher your arms rise the more challenging the physics of pinning your center of gravity. Your head should remain dead centered and fully upright. I've seen some head tilted back scratch spins but frankly watching them makes ME dizzy.
The end of the spin can be either gradual or checked-out. Smile!