If I'm reading you right, you have some good points. I would agree that if the style has something, we (or at least I) ought to learn it.
When I did Muay Thai in my university, essentially there were 2 groups. There was the main group, and then a side group that went at things a lot harder and in more detail later. This way, those who wanted to or were able to could go in deeper and harder could, but those who couldn't or wouldn't weren't forced to go too far beyond their capacity.
In Aikido, whenever possible I work with higher ranks after class to go a bit harder (this is encouraged by my sensei).
I suppose it would be up to individuals to find sempai to work with to go the extra distance, or to go straight to the sensei.