More important than the number of rakes, is the willingness of the zone to convert the rakes. SCR has shown reluctance to convert any of it's 24 coachers to LHB. SWR is facing a shortage of coaches. But SCR and SWR have excellent maintenance of their trains and LHB/no-LHB is not really a big concern for many right away.
SR faced some backlash from passengers about reduced UR, when the converted Pandian to LHB. Though they have converted some trains to LHB after that, even they are reluctant to convert any of their highly popular, 24 coach trains to LHB.