(Presumably this covers the eventuality that a control zone overlies the NTA but does not come down to SFC.)
Control Zones are from SFC up. Control Areas do not come down to the SFC.
Broadcast Areas are not CTAF.
I think you have muddied things to the extent that I recommend all read the 28 June 12 AIP ENR 1.4-7 to understand the real situation.
The problem with the so-called "Large CTAF" was that not having a vertical limit, pilots were unsure at what level overflying they should be on the FIA or Large CTAF. These Broadcast Areas remove that confusion.
A CTAF is just that - a Common Traffic Advisory
Frequency. They are not a defined volume of airspace, simply a frequency to be on when in the vicinity (WI 10NM) of an AD/ALA.