The shows had to be modified to fit an American attention span, and would be 30-45 minutes long with 5-7 parts. Tricks like sword dancing, which was inspired by Tunisian pot dancing, and tray balancing, presumably inspired by Moroccan tradition, were added for spectacle to wow audiences and became arts in their own right. Here's Shira's article about the 3 styles most common in the USA qued up to the bit about Am Cab set structure . One reason for going fast-slow-fast-slow-fast..... is because American audiences aren't familiar with the music and need help knowing when one song stops and the next starts. (This is a normal thing for any music we are unfamiliar with.) Shems' article has a playlist (the link on the page isn't working, so you can get to it from here.)
Finger cymbal playing was a requirement for pros. Partly because of expectations and partly because they really do help get the audience's attention in a loud restaurant. Veil work is also quite extensive, usually done to a rhumba or similar rhythm, and the dancer would start wrapped in her veil (one reason a veil isn't usually considered an adequate cover-up outside of tribal-centric shows). I like it if the costume is mostly visible under said wrap, so people unfamiliar with the style don't think more things will come off next.
Floor work was also an integral part, usually performed to a chifititelli. As I mentioned, a lot of the American style at the time was influenced by the Turkish style, but dancers here also developed their own myths around it. Some did intense research into the cultures and folk dances of the Middle East, some created their own fantasies. In the climate of feminine sexual empowerment movement and hippie-dom some of these stories flourished and drew people to the dance for a wide variety of reasons. Many found growth that they needed and were struggling to achieve without the dance.
The East coast and West coast styling differed, on the West coast Jamilla Salimpour was a very influential teacher, and her troupe, Bal Anat, was formed with her circus background to perform at Renaissance/ Fantasy fairs. She taught some amazing dancers of the era, including Aida. Jamila would be the great grandma of tribal style, which we'll get to in a few weeks. You can learn about many of the big names in this style from Amaya's DVD American Bellydance Legends.