D needs a definition change. The current definition of D rank is redundant with E, since they essentially mean the same thing (don't use these mons in RU). D rank should be a place for Pokemon with a niche in RU, but a restricted one. They "cost more than they are worth," cost being a team slot.
This way it wouldn't be as repugnant to place anything in D rank, since they still do have a place in RU. With this definition change, a lot of the current C ranks can possibly move down to D, since C is messy, imo, cluttered with decent to mediocre Pokemon.
I am also open to lars, "soft limit," it's really interesting.
Why is Primeape in B rank x_x