This document seems ready to me.

I did have one question - RFC7285 says that servers MUST support one of the numeric or ordinal cost-modes. It wasn't entirely clear to me whether it's intended that that remain the case, but I assume it is, so that e.g. it'd be invalid to have a server that only supports some new "foo" cost mode. If that's the case, then this draft is fine. If something else was intended then I guess a bit more text on that would be needed.