My question to the technical divers of the sport is what do you wish you where taught from the beginning.
What a great question and I wish I'd seen it sooner.
Since your OP and the title thread are slightly different to me, I'll try to answer the title of the thread as that was what attracted me first.
What do you wish you could teach a recreational diver?
To me each new diver is different and I really try to tailor my courses to the diver since I have the luxury to teach when I want and who I want.
I believe most rec. courses provide a good framework to teach a new diver, however to fill the gaps of the framework the biggest variable in my course is the student.
My prospective students can mostly be categorized in three groups:
A: I want to learn to dive! Usually neighbors, coworkers or friends who hear me talk about diving (Most desirable)
B: How long does it take and how much does it cost to learn to dive? Usually people looking to find the cheapest class and mentioning Groupon!
C: I need to learn to dive by
insert unreasonable date here! Usually people going on a vacation and in a hurry (Least desirable)
I teach the same course to each type, but their attention span and goals are different.
By the time the type A student is in class they will already have an understanding that class is just the beginning. They will usually stick around after being certified and become dive buddies. They can be mentored beyond class.
The type B student can be converted to a type A, but more often than not I'm not successful at it due to price!
The type C student does not care about price, but a compressed schedule. While they may grasp all the concepts, demonstrate the skills and spend the same amount of total time in the water and class as type A. Once certified and off to their vacation they will not go beyond what they learned and often regress, forget and or develop bad habits due to inactivity.
So to answer both of your questions, I wish I was told exactly what I needed to work on the most the moment I finished my OW and provided a way to do just that! Instead of being treated as a cash cow and offered a bunch of courses that may or may not apply to my current needs.
For example, I was offered a nitrox course and AOW right after OW for a discounted price. BTW, I was a type B student going into my OW class so I took the discounted AOW/Nitrox class. However I couldn't properly hover motionless and sucked more air than a vacuum cleaner so longer NDLs were a pipe dream. Yes, I learned a few things from my AOW and the theory behind the Nitrox class stayed with me until I needed it, but neither class helped me become a better diver at the time or addressed my specific needs.