Hi,
I can give you a beginners perspective. I have been going to group dance lessons for a couple of years mostly to please my wife. About 2 months ago I finally said to myself, if I am going to do this I am going to learn to dance.
We have group lessons every Monday which consists of two one hour dances which consists of something like a fox trot and east coast swing. It is impossible to say which dances to start with because we start two new dances every month. So, it all depends on which month the student comes as to what dance they start with.
Our instructor focuses mainly on basic dance steps (bronze stuff). By the end of each month, we learn enough to do about a 45 to 60 second routine. My wife and I went to another studio where we spent one hour totally on hip, feet, etc. with three steps of the cha cha walking forward. We never went back; we weren't ready for that and it wasn't fun. There are other instructors at our independent studio that teach on different days and teach more style. Our instructor has over fifty students in each class. The other instructor has about eight. The people in our class that want to progress, start taking private lessons (like we finally did.) In the end, our teacher always ends up with more winners at competitions.
As a consumer and a beginner, I don't want to pay for private lessons to learn dance routines. I want learn the steps in the group class and learn style and technique for those steps in a private or semi-private lesson (with my wife.)
Our instructor has said that her teaching method depends on what part of the country or world where she is teaching. When she taught in Russia, every single student was taking lessons for competition; social dancing was unheard of at her studio there. Similarly, she said that when she taught in New York / New Jersey they wanted more style and technique. When she came down south in Florida (with lots of retirees) she said that she was surprised and delighted that most people just wanted to learn social dancing. She had to change her teaching method for more "moves" than technique in the group lessons. Currently out of the fifty people in the dance class about forty just want to get good enough to go out to the dance party and have fun. From my limited knowledge, I can see that the form is not correct, there are a lot of missteps, some are off beat but everyone is having fun - beginners and experienced competitive dancers.
I come from a tennis background so I can relate it to the a tennis teaching pro. Some pros teach tennis at a hotel or resort to people on vacation; the goal is to get them to be able to hit the ball back and forth. Then the teach a smidgen of strategy for doubles. However, some teaching pros are always looking for the next prodigy. They go to junior tennis tournaments and scout out 10 and 12 year old kids that really show talent. They are looking to develop the next Roger Federer or Rafael Nadal. They teach the intricacies of the game.
In summary, you have to figure out who you want to teach and what the market where you are wants.