This 'doesn't scale well with skill' is a subset of a different problem, 'you can relatively easily earn much more points that the rank system was designed for due to all the new opportunities' (even with BH moved back).
Weaving the BH ranks into captain ranks system is not a bad idea, but I don't like it since it would put all eggs into a single basket, that is, tie progression in both things to a single metric.
The Racketeer requirement is indeed intended to postpone the rank by one more month, although perhaps the solution is too heavy handed. The key unlock is Rank 2 anyway for Car Thieves, so perhaps alternative change can be undertaken: to move BH's to Rank 1.