This all sounds great.
I began to write a roles RFC way back in the day, but
stopped when our work went in a different direction.
That effort could be resurrected.
All the dynamic magic, usage with CoS, etc can still be a
differentiating benefit of FDS (unless Red Hat wants that to be part
of the standard).
There's a lot of work to implement this stuff and to make it work
efficiently (and to ensure that it's well tested, documented and supported).
I don't see any value to RH in restricting what is included in a standard.