They probably wouldn't let me in the ladies' dressing rooms at the dancesport events. No, I haven't tried - not even in the name of that most self-sanctified of all callings - Journalism! But I have a pretty good idea about what I would see anyway (not that that's ever kept me from taking a good look before...).
There'd be women of all ages for pro-am events, but the competitive pros are between about 18 on the low end to about 40 or so on the high end. Latin in particular is very physically demanding, so the women retire fairly young. Then they typically go on to get their own studios and teach, or take students to pro-am competitions, or they become judges or other officials for dance events. They don't have anywhere near the coaching opportunities men do, because the amateur competitors in my experience number around two women for every man.
If you're looking for "diversity" this isn't the place. If you were expecting to see a lot of Latins in the Latin dancing, sorry. Competing is expensive for amateurs, especially on the road. (Even top pros can't make much money consistently - the purses just aren't there.) So if you look into the backgrounds of top amateur dancers you'll find that they are often well compensated professional women and all that that implies demographically. In particular, it seems lily-white - I recall two black male pros from Miami and a woman amateur from DC, but that's about it, and the audience isn't much different in my experience.
Physically the amateurs would be all over the map, with some downright hefty girls competing. Heights ranging from tiny 6 year olds to 6' plus. The pros all seem to be in a range of about 5'2" to 5'10", roughly estimated, and they're buff - the years of training and practice trim and shape them as few other things can. But they still look like women.
Well, some of them want to look more like women. There's falsies, particularly in the standard/smooth where the girls are more covered. For the rest there's Wonderbras, but there's only so much that upholstery can do. The meatier amateurs are often willing to let it all hang out, but I don't recall seeing many pros over a B cup or so. My goddess Charlotte Jorgensen from "Dancing with the Stars" is typical, and that's fine with me.
There would be lots of instant tanning compound. A lot of those dancers are naturally very fair-skinned, and bright lights on the floor make them all but disappear. So you'll see many "tanned" palms and soles, and no doubt some strange looking effects once you get to what the costumes cover. I hear that the stuff is expensive too.
Likewise the makeup is overdone for cameras and lights. They wear enough so that close up they're almost clownlike, but somehow they keep it from running during long energetic dance events. Like in theater and on TV, some of the men wear it too. I can only imagine how hot that must be.
The hair! Good grief, they way most of them do it you'd think it would never move again. It's usually longer than what you see, anyway. It's true that you don't want anyone stepping on it or to have it dragging on the ground (these girls are flexible), nor do you want it used as a weapon, but I think I'd rather have them all wearing helmets than what they do wear. Even the women with short hair plaster it down. Many of them dye it bright colors.
Psst, wanna talk underwear? Well, experience has shown that it's necessary to have some rules what with the short skirts and very flexible women out on the floor. A certain minimum amount of coverage is required in the rules to avoid this. Stockings are found, regular or fishnet, but they don't last long.
As for dresses, the ones for smooth or standard dances(waltz, etc.) are long and snug in the body. They'll come nearly to the floor. There might be a lot of skin showing, or long slits in the skirt, but the dances are more about grace than glamour so there's a practical limit.
The Latin outfits are another thing. Even the men usually wear something open all the way down the front, and the women...well, there's not much there, They use strategically placed transparent straps to hold things together, and I wouldn't be surprised if some used glue in places.
("Wardrobe malfunctions"? You betcha - I've seen a few. Usually it's a heel caught in the hem of a dress, and in an energetic dance like jive they can do this with a very short skirt. I've been told that a top competitor once had a top split right down the front in the middle of a number, but she managed to keep it together long enough to finish and get off the floor. There's no stage, and nowhere to hide - the only way out is through the audience)
Now really, what other blog could offer you such inside dope with a twisted angle? Or would resort to such a lame device to end a post?