The simplest of answer, for me, would be that if a school is going to be run like a business, then I need to be paid like a business would pay me. And within those expectations of that business. Example: If a community and district is allowed to treat me like I am a customer service worker then pay me hourly for everything I do including outside the classroom. If a community and district is going to call me an expert in my field, then pay me like most experts are paid for their craft.
I have worked for head directors that maxed out the 10 hour rule, added 6 extra marching contests, winter guard, winter drum line, 4 pre C&SR contests, all region, and solo and ensemble. And yes I've moved on from those jobs. And yes, I appreciate what I learned at those jobs. However with all that time I spent at work, my stipend didn't get higher, I didn't get a pay raise and this was all set by the head director that doesn't have control over my pay check. But I wasn't allowed to say no (well, not with out there being any kind of repercussions for it anyway) because these were the expectations they set to administration and of course the administration was ok with it because they were not required to pay more so long as they gave me my stipend.
Soooo many factors go into that question though, but that's why I like talks like this. It's a good start, but I do believe there are other talks that need to be added to it to have a full idea of what is "fair".