True, CN has an NDB and RNAV approach but you'll still need to climb to start the approach and you may as well do that on the way from Bankstown - which is only a few minutes (the time you'll need to climb) away. ILS will need to be done at Richmond anyway, plus you'll need to do SIDs and STARs (which are BK based, not CN).
Can't do better than Bill Whitworth for the MECIR. He's a legend for a reason! Sure, JWW desperately needs a new paint job - but it's always flying, so probably won't ever get it!
Ted