I read somewhere that there was a proposal for new ranks in the RAF to have this structure:
Ensign, Lieutenant, Flight-Leader, Squadron-Leader, Reeve, Banneret, Fourth-Ardian, Third-Ardian, Second-Ardian, Ardian, Air Marshal.
A further suggestion was a variation on the above:
Ensign, Lieutenant, Flight-Leader, Squadron-Leader, Wing-Leader, Leader, Flight Ardian, Squadron Ardian, Wing Ardian, Ardian, Air Marshal.
Ardian
Reeve
Banneret