While I completely agree that there are Unix idioms that could go by the wayside, the team is already taking on an enormous project. Reinventing standard practices at the same time (and the ridiculous bike shedding that would ensue) seems like an even more impossible task.

Strongly agreed.

Especially since multiple successors to Unix already exist -- notably, Plan 9 and Inferno.

If you have ideas, then you should pitch them on the corresponding GitHub projects.