Hmmm. Wasn't this supposed to already be available "officially"? What happened to that?
Great idea.
I have one suggestion, and that is to break the training down into skill levels. For example, training for somebody who is new to flight sims would have to be completely different than for somebody who's been around for a while, but has some specific things they'd like to improve upon. The trainers would likewise need to have different skill level minimums. So allow somebody to sign up for beginner, intermediate, or advanced training in any of the subjects, or perhaps classify the subject based upon skill level. You could have people who train basic ACM (or whatever you want to call it) for newbies, and have intermediate classes for say E-retention, and the advanced pilots could sign up for advanced topics like Turn-fighting in a P-38.
That seems a bit unwieldy though, so I think I prefer allowing the trainer and the trainees to select their level of competency so they can match their skill levels.